Adding upstream version 3.2.0.upstream/3.2.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

50 files changed, 953 insertions, 635 deletions

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..ce54d6f
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,66 @@
+name: pgcli
+
+on:
+  pull_request:
+    paths-ignore:
+      - '**.rst'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        python-version: [3.6, 3.7, 3.8, 3.9]
+
+    services:
+      postgres:
+        image: postgres:9.6
+        env:
+          POSTGRES_USER: postgres
+          POSTGRES_PASSWORD: postgres
+        ports:
+            - 5432:5432
+        options: >-
+          --health-cmd pg_isready
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v2
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install requirements
+        run: |
+          pip install -U pip setuptools
+          pip install --no-cache-dir .
+          pip install -r requirements-dev.txt
+          pip install keyrings.alt>=3.1
+
+      - name: Run unit tests
+        run: coverage run --source pgcli -m py.test
+
+      - name: Run integration tests
+        env:
+            PGUSER: postgres
+            PGPASSWORD: postgres
+
+        run: behave tests/features --no-capture
+
+      - name: Check changelog for ReST compliance
+        run: rst2html.py --halt=warning changelog.rst >/dev/null
+
+      - name: Run Black
+        run: pip install black && black --check .
+        if: matrix.python-version == '3.6'
+
+      - name: Coverage
+        run: |
+          coverage combine
+          coverage report
+          codecov
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index b970ac5..9e27ab8 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,6 +1,6 @@
 repos:
 -   repo: https://github.com/psf/black
-    rev: stable
+    rev: 21.5b0
     hooks:
     - id: black
       language_version: python3.7
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 8d50fbd..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,51 +0,0 @@
-dist: xenial
-
-sudo: required
-
-language: python
-
-python:
-  - "3.6"
-  - "3.7"
-  - "3.8"
-  - "3.9-dev"
-
-before_install:
-  - which python
-  - which pip
-  - pip install -U setuptools
-
-install:
-  - pip install --no-cache-dir .
-  - pip install -r requirements-dev.txt
-  - pip install keyrings.alt>=3.1
-
-script:
-  - set -e
-  - coverage run --source pgcli -m py.test
-  - cd tests
-  - behave --no-capture
-  - cd ..
-  # check for changelog ReST compliance
-  - rst2html.py --halt=warning changelog.rst >/dev/null
-  # check for black code compliance, 3.6 only
-  - if [[ "$TRAVIS_PYTHON_VERSION" == "3.6" ]]; then pip install black && black --check . ; else echo "Skipping black for $TRAVIS_PYTHON_VERSION"; fi
-  - set +e
-
-after_success:
-  - coverage combine
-  - codecov
-
-notifications:
-  webhooks:
-    urls:
-      - YOUR_WEBHOOK_URL
-    on_success: change  # options: [always|never|change] default: always
-    on_failure: always  # options: [always|never|change] default: always
-    on_start: false     # default: false
-
-services:
-  - postgresql
-
-addons:
-  postgresql: "9.6"
diff --git a/AUTHORS b/AUTHORS
index baaf758..bcfba6a 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -114,6 +114,10 @@ Contributors:
     * Tom Caruso (tomplex)
     * Jan Brun Rasmussen (janbrunrasmussen)
     * Kevin Marsh (kevinmarsh)
+    * Eero Ruohola (ruohola)
+    * Miroslav Šedivý (eumiro)
+    * Eric R Young (ERYoung11) 
+    * Paweł Sacawa (psacawa)
 
 Creator:
 --------
diff --git a/DEVELOP.rst b/DEVELOP.rst
index 18adf9c..e262823 100644
--- a/DEVELOP.rst
+++ b/DEVELOP.rst
@@ -170,7 +170,7 @@ Troubleshooting the integration tests
 - Make sure postgres instance on localhost is running
 - Check your ``pg_hba.conf`` file to verify local connections are enabled
 - Check `this issue <https://github.com/dbcli/pgcli/issues/945>`_ for relevant information.
-- Contact us on `gitter <https://gitter.im/dbcli/pgcli/>`_ or `file an issue <https://github.com/dbcli/pgcli/issues/new>`_.
+- `File an issue <https://github.com/dbcli/pgcli/issues/new>`_.
 
 Coding Style
 ------------
diff --git a/README.rst b/README.rst
index d593427..95137f7 100644
--- a/README.rst
+++ b/README.rst
@@ -1,7 +1,7 @@
 A REPL for Postgres
 -------------------
 
-|Build Status| |CodeCov| |PyPI| |Landscape| |Gitter|
+|Build Status| |CodeCov| |PyPI| |Landscape|
 
 This is a postgres client that does auto-completion and syntax highlighting.
 
@@ -62,32 +62,32 @@ For more details:
     Usage: pgcli [OPTIONS] [DBNAME] [USERNAME]
 
     Options:
-      -h, --host TEXT         Host address of the postgres database.
-      -p, --port INTEGER      Port number at which the postgres instance is
-                              listening.
-      -U, --username TEXT     Username to connect to the postgres database.
-      -u, --user TEXT         Username to connect to the postgres database.
-      -W, --password          Force password prompt.
-      -w, --no-password       Never prompt for password.
-      --single-connection     Do not use a separate connection for completions.
-      -v, --version           Version of pgcli.
-      -d, --dbname TEXT       database name to connect to.
-      --pgclirc PATH          Location of pgclirc file.
-      -D, --dsn TEXT          Use DSN configured into the [alias_dsn] section of
-                              pgclirc file.
-      --list-dsn              list of DSN configured into the [alias_dsn] section
-                              of pgclirc file.
-      --row-limit INTEGER     Set threshold for row limit prompt. Use 0 to disable
-                              prompt.
-      --less-chatty           Skip intro on startup and goodbye on exit.
-      --prompt TEXT           Prompt format (Default: "\u@\h:\d> ").
-      --prompt-dsn TEXT       Prompt format for connections using DSN aliases
-                              (Default: "\u@\h:\d> ").
-      -l, --list              list available databases, then exit.
-      --auto-vertical-output  Automatically switch to vertical output mode if the
-                              result is wider than the terminal width.
-      --warn / --no-warn      Warn before running a destructive query.
-      --help                  Show this message and exit.
+      -h, --host TEXT            Host address of the postgres database.
+      -p, --port INTEGER         Port number at which the postgres instance is
+                                 listening.
+      -U, --username TEXT        Username to connect to the postgres database.
+      -u, --user TEXT            Username to connect to the postgres database.
+      -W, --password             Force password prompt.
+      -w, --no-password          Never prompt for password.
+      --single-connection        Do not use a separate connection for completions.
+      -v, --version              Version of pgcli.
+      -d, --dbname TEXT          database name to connect to.
+      --pgclirc FILE             Location of pgclirc file.
+      -D, --dsn TEXT             Use DSN configured into the [alias_dsn] section
+                                 of pgclirc file.
+      --list-dsn                 list of DSN configured into the [alias_dsn]
+                                 section of pgclirc file.
+      --row-limit INTEGER        Set threshold for row limit prompt. Use 0 to
+                                 disable prompt.
+      --less-chatty              Skip intro on startup and goodbye on exit.
+      --prompt TEXT              Prompt format (Default: "\u@\h:\d> ").
+      --prompt-dsn TEXT          Prompt format for connections using DSN aliases
+                                 (Default: "\u@\h:\d> ").
+      -l, --list                 list available databases, then exit.
+      --auto-vertical-output     Automatically switch to vertical output mode if
+                                 the result is wider than the terminal width.
+      --warn [all|moderate|off]  Warn before running a destructive query.
+      --help                     Show this message and exit.
 
 ``pgcli`` also supports many of the same `environment variables`_ as ``psql`` for login options (e.g. ``PGHOST``, ``PGPORT``, ``PGUSER``, ``PGPASSWORD``, ``PGDATABASE``).
 
@@ -352,8 +352,8 @@ interface to Postgres database.
 Thanks to all the beta testers and contributors for your time and patience. :)
 
 
-.. |Build Status| image:: https://api.travis-ci.org/dbcli/pgcli.svg?branch=master
-    :target: https://travis-ci.org/dbcli/pgcli
+.. |Build Status| image:: https://github.com/dbcli/pgcli/workflows/pgcli/badge.svg
+    :target: https://github.com/dbcli/pgcli/actions?query=workflow%3Apgcli
 
 .. |CodeCov| image:: https://codecov.io/gh/dbcli/pgcli/branch/master/graph/badge.svg
    :target: https://codecov.io/gh/dbcli/pgcli
@@ -366,7 +366,3 @@ Thanks to all the beta testers and contributors for your time and patience. :)
 .. |PyPI| image:: https://img.shields.io/pypi/v/pgcli.svg
     :target: https://pypi.python.org/pypi/pgcli/
     :alt: Latest Version
-
-.. |Gitter| image:: https://badges.gitter.im/Join%20Chat.svg
-    :target: https://gitter.im/dbcli/pgcli?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge
-    :alt: Gitter Chat
diff --git a/Vagrantfile b/Vagrantfile
index 0313520..297e70a 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -1,5 +1,7 @@
 # -*- mode: ruby -*-
 # vi: set ft=ruby :
+# 
+#
 
 Vagrant.configure(2) do |config|
 
@@ -9,20 +11,23 @@ Vagrant.configure(2) do |config|
   pgcli_description = "Postgres CLI with autocompletion and syntax highlighting"
 
   config.vm.define "debian" do |debian|
-    debian.vm.box = "chef/debian-7.8"
+    debian.vm.box = "bento/debian-10.8"
     debian.vm.provision "shell", inline: <<-SHELL
-    echo "-> Building DEB on `lsb_release -s`"
+    echo "-> Building DEB on `lsb_release -d`"
     sudo apt-get update
     sudo apt-get install -y libpq-dev python-dev python-setuptools rubygems
-    sudo easy_install pip
-    sudo pip install virtualenv virtualenv-tools
+    sudo apt install -y python3-pip
+    sudo pip3 install --no-cache-dir virtualenv virtualenv-tools3
+    sudo apt-get install -y ruby-dev
+    sudo apt-get install -y git
+    sudo apt-get install -y rpm librpmbuild8
+
     sudo gem install fpm
+
     echo "-> Cleaning up old workspace"
-    rm -rf build
+    sudo rm -rf build
     mkdir -p build/usr/share
     virtualenv build/usr/share/pgcli
-    build/usr/share/pgcli/bin/pip install -U pip distribute
-    build/usr/share/pgcli/bin/pip uninstall -y distribute
     build/usr/share/pgcli/bin/pip install /pgcli
 
     echo "-> Cleaning Virtualenv"
@@ -45,24 +50,59 @@ Vagrant.configure(2) do |config|
         --url https://github.com/dbcli/pgcli \
         --description "#{pgcli_description}" \
         --license 'BSD'
+
     SHELL
   end
 
+  
+# This is considerably more messy than the debian section.  I had to go off-standard to update
+# some packages to get this to work.
+
   config.vm.define "centos" do |centos|
-    centos.vm.box = "chef/centos-7.0"
+
+    centos.vm.box = "bento/centos-7.9"
+    centos.vm.box_version = "202012.21.0"
     centos.vm.provision "shell", inline: <<-SHELL
     #!/bin/bash
-    echo "-> Building RPM on `lsb_release -s`"
-    sudo yum install -y rpm-build gcc ruby-devel postgresql-devel python-devel rubygems
-    sudo easy_install pip
-    sudo pip install virtualenv virtualenv-tools
-    sudo gem install fpm
+    echo "-> Building RPM on `hostnamectl | grep "Operating System"`"
+    export PATH=/usr/local/rvm/gems/ruby-2.6.3/bin:/usr/local/rvm/gems/ruby-2.6.3@global/bin:/usr/local/rvm/rubies/ruby-2.6.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/rvm/bin:/root/bin
+    echo "PATH -> " $PATH
+
+#####
+### get base updates
+
+    sudo yum install -y rpm-build gcc postgresql-devel python-devel  python3-pip git python3-devel
+
+######
+### install FPM, which we need to install to get an up-to-date version of ruby, which we need for git
+
+    echo "-> Get FPM installed"
+    # import the necessary GPG keys
+    gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+    sudo gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+    # install RVM
+    sudo curl -sSL https://get.rvm.io | sudo bash -s stable
+    sudo usermod -aG rvm vagrant
+    sudo usermod -aG rvm root
+    sudo /usr/local/rvm/bin/rvm alias create default 2.6.3
+    source /etc/profile.d/rvm.sh
+    
+    # install a newer version of ruby.  centos7 only comes with ruby2.0.0, which isn't good enough for git.
+    sudo yum install -y ruby-devel
+    sudo /usr/local/rvm/bin/rvm install 2.6.3
+    
+    #
+    # yes,this gives an error about generating doc but we don't need the doc. 
+
+    /usr/local/rvm/gems/ruby-2.6.3/wrappers/gem install fpm
+
+######
+
+    sudo pip3 install virtualenv virtualenv-tools3
     echo "-> Cleaning up old workspace"
     rm -rf build
     mkdir -p build/usr/share
     virtualenv build/usr/share/pgcli
-    build/usr/share/pgcli/bin/pip install -U pip distribute
-    build/usr/share/pgcli/bin/pip uninstall -y distribute
     build/usr/share/pgcli/bin/pip install /pgcli
 
     echo "-> Cleaning Virtualenv"
@@ -74,9 +114,9 @@ Vagrant.configure(2) do |config|
     find build -iname '*.pyc' -delete
     find build -iname '*.pyo' -delete
 
+    cd /home/vagrant
     echo "-> Creating PgCLI RPM"
-    echo $PATH
-    sudo /usr/local/bin/fpm -t rpm -s dir -C build -n pgcli -v #{pgcli_version} \
+    /usr/local/rvm/gems/ruby-2.6.3/gems/fpm-1.12.0/bin/fpm -t rpm -s dir -C build -n pgcli -v #{pgcli_version} \
         -a all \
         -d postgresql-devel \
         -d python-devel \
@@ -86,8 +126,13 @@ Vagrant.configure(2) do |config|
         --url https://github.com/dbcli/pgcli \
         --description "#{pgcli_description}" \
         --license 'BSD'
-    SHELL
+
+
+  SHELL
+
+
   end
 
+
 end
 
diff --git a/changelog.rst b/changelog.rst
index ec50635..d732088 100644
--- a/changelog.rst
+++ b/changelog.rst
@@ -1,3 +1,37 @@
+TBD
+=====
+
+Features:
+---------
+
+Bug fixes:
+----------
+
+3.2.0 
+=====
+
+Release date: 2021/08/23
+
+Features:
+---------
+
+* Consider `update` queries destructive and issue a warning. Change
+  `destructive_warning` setting to `all|moderate|off`, vs `true|false`. (#1239)
+* Skip initial comment in .pg_session even if it doesn't start with '#'
+* Include functions from schemas in search_path. (`Amjith Ramanujam`_)
+
+Bug fixes:
+----------
+
+* Fix issue where `syntax_style` config value would not have any effect. (#1212)
+* Fix crash because of not found `InputMode.REPLACE_SINGLE` with prompt-toolkit < 3.0.6
+* Fix comments being lost in config when saving a named query. (#1240)
+* Fix IPython magic for ipython-sql >= 0.4.0
+* Fix pager not being used when output format is set to csv. (#1238)
+* Add function literals random, generate_series, generate_subscripts
+* Fix ANSI escape codes in first line make the cli choose expanded output incorrectly
+* Fix pgcli crashing with virtual `pgbouncer` database. (#1093)
+
 3.1.0
 =====
 
diff --git a/pgcli/__init__.py b/pgcli/__init__.py
index f5f41e5..1173108 100644
--- a/pgcli/__init__.py
+++ b/pgcli/__init__.py
@@ -1 +1 @@
-__version__ = "3.1.0"
+__version__ = "3.2.0"
diff --git a/pgcli/completion_refresher.py b/pgcli/completion_refresher.py
index cf0879f..1039d51 100644
--- a/pgcli/completion_refresher.py
+++ b/pgcli/completion_refresher.py
@@ -3,10 +3,9 @@ import os
 from collections import OrderedDict
 
 from .pgcompleter import PGCompleter
-from .pgexecute import PGExecute
 
 
-class CompletionRefresher(object):
+class CompletionRefresher:
 
     refreshers = OrderedDict()
 
@@ -27,6 +26,10 @@ class CompletionRefresher(object):
                     has completed the refresh. The newly created completion
                     object will be passed in as an argument to each callback.
         """
+        if executor.is_virtual_database():
+            # do nothing
+            return [(None, None, None, "Auto-completion refresh can't be started.")]
+
         if self.is_refreshing():
             self._restart_refresh.set()
             return [(None, None, None, "Auto-completion refresh restarted.")]
@@ -141,7 +144,7 @@ def refresh_casing(completer, executor):
         with open(casing_file, "w") as f:
             f.write(casing_prefs)
     if os.path.isfile(casing_file):
-        with open(casing_file, "r") as f:
+        with open(casing_file) as f:
             completer.extend_casing([line.strip() for line in f])
 
 
diff --git a/pgcli/config.py b/pgcli/config.py
index 0fc42dd..22f08dc 100644
--- a/pgcli/config.py
+++ b/pgcli/config.py
@@ -3,6 +3,8 @@ import shutil
 import os
 import platform
 from os.path import expanduser, exists, dirname
+import re
+from typing import TextIO
 from configobj import ConfigObj
 
 
@@ -16,11 +18,15 @@ def config_location():
 
 
 def load_config(usr_cfg, def_cfg=None):
-    cfg = ConfigObj()
-    cfg.merge(ConfigObj(def_cfg, interpolation=False))
-    cfg.merge(ConfigObj(expanduser(usr_cfg), interpolation=False, encoding="utf-8"))
+    # avoid config merges when possible. For writing, we need an umerged config instance.
+    # see https://github.com/dbcli/pgcli/issues/1240 and https://github.com/DiffSK/configobj/issues/171
+    if def_cfg:
+        cfg = ConfigObj()
+        cfg.merge(ConfigObj(def_cfg, interpolation=False))
+        cfg.merge(ConfigObj(expanduser(usr_cfg), interpolation=False, encoding="utf-8"))
+    else:
+        cfg = ConfigObj(expanduser(usr_cfg), interpolation=False, encoding="utf-8")
     cfg.filename = expanduser(usr_cfg)
-
     return cfg
 
 
@@ -44,12 +50,16 @@ def upgrade_config(config, def_config):
     cfg.write()
 
 
+def get_config_filename(pgclirc_file=None):
+    return pgclirc_file or "%sconfig" % config_location()
+
+
 def get_config(pgclirc_file=None):
     from pgcli import __file__ as package_root
 
     package_root = os.path.dirname(package_root)
 
-    pgclirc_file = pgclirc_file or "%sconfig" % config_location()
+    pgclirc_file = get_config_filename(pgclirc_file)
 
     default_config = os.path.join(package_root, "pgclirc")
     write_default_config(default_config, pgclirc_file)
@@ -62,3 +72,28 @@ def get_casing_file(config):
     if casing_file == "default":
         casing_file = config_location() + "casing"
     return casing_file
+
+
+def skip_initial_comment(f_stream: TextIO) -> int:
+    """
+    Initial comment in ~/.pg_service.conf is not always marked with '#'
+    which crashes the parser. This function takes a file object and
+    "rewinds" it to the beginning of the first section,
+    from where on it can be parsed safely
+
+    :return: number of skipped lines
+    """
+    section_regex = r"\s*\["
+    pos = f_stream.tell()
+    lines_skipped = 0
+    while True:
+        line = f_stream.readline()
+        if line == "":
+            break
+        if re.match(section_regex, line) is not None:
+            f_stream.seek(pos)
+            break
+        else:
+            pos += len(line)
+            lines_skipped += 1
+    return lines_skipped
diff --git a/pgcli/magic.py b/pgcli/magic.py
index f58f415..6e58f28 100644
--- a/pgcli/magic.py
+++ b/pgcli/magic.py
@@ -25,7 +25,11 @@ def pgcli_line_magic(line):
     if hasattr(sql.connection.Connection, "get"):
         conn = sql.connection.Connection.get(parsed["connection"])
     else:
-        conn = sql.connection.Connection.set(parsed["connection"])
+        try:
+            conn = sql.connection.Connection.set(parsed["connection"])
+        # a new positional argument was added to Connection.set in version 0.4.0 of ipython-sql
+        except TypeError:
+            conn = sql.connection.Connection.set(parsed["connection"], False)
 
     try:
         # A corresponding pgcli object already exists
@@ -43,7 +47,7 @@ def pgcli_line_magic(line):
         conn._pgcli = pgcli
 
     # For convenience, print the connection alias
-    print("Connected: {}".format(conn.name))
+    print(f"Connected: {conn.name}")
 
     try:
         pgcli.run_cli()
diff --git a/pgcli/main.py b/pgcli/main.py
index b146898..5135f6f 100644
--- a/pgcli/main.py
+++ b/pgcli/main.py
@@ -2,8 +2,9 @@ import platform
 import warnings
 from os.path import expanduser
 
-from configobj import ConfigObj
+from configobj import ConfigObj, ParseError
 from pgspecial.namedqueries import NamedQueries
+from .config import skip_initial_comment
 
 warnings.filterwarnings("ignore", category=UserWarning, module="psycopg2")
 
@@ -20,12 +21,12 @@ import datetime as dt
 import itertools
 import platform
 from time import time, sleep
-from codecs import open
 
 keyring = None  # keyring will be loaded later
 
 from cli_helpers.tabular_output import TabularOutputFormatter
 from cli_helpers.tabular_output.preprocessors import align_decimals, format_numbers
+from cli_helpers.utils import strip_ansi
 import click
 
 try:
@@ -62,6 +63,7 @@ from .config import (
     config_location,
     ensure_dir_exists,
     get_config,
+    get_config_filename,
 )
 from .key_bindings import pgcli_bindings
 from .packages.prompt_utils import confirm_destructive_query
@@ -122,7 +124,7 @@ class PgCliQuitError(Exception):
     pass
 
 
-class PGCli(object):
+class PGCli:
     default_prompt = "\\u@\\h:\\d> "
     max_len_prompt = 30
 
@@ -175,7 +177,11 @@ class PGCli(object):
         # Load config.
         c = self.config = get_config(pgclirc_file)
 
-        NamedQueries.instance = NamedQueries.from_config(self.config)
+        # at this point, config should be written to pgclirc_file if it did not exist. Read it.
+        self.config_writer = load_config(get_config_filename(pgclirc_file))
+
+        # make sure to use self.config_writer, not self.config
+        NamedQueries.instance = NamedQueries.from_config(self.config_writer)
 
         self.logger = logging.getLogger(__name__)
         self.initialize_logging()
@@ -201,8 +207,11 @@ class PGCli(object):
         self.syntax_style = c["main"]["syntax_style"]
         self.cli_style = c["colors"]
         self.wider_completion_menu = c["main"].as_bool("wider_completion_menu")
-        c_dest_warning = c["main"].as_bool("destructive_warning")
-        self.destructive_warning = c_dest_warning if warn is None else warn
+        self.destructive_warning = warn or c["main"]["destructive_warning"]
+        # also handle boolean format of destructive warning
+        self.destructive_warning = {"true": "all", "false": "off"}.get(
+            self.destructive_warning.lower(), self.destructive_warning
+        )
         self.less_chatty = bool(less_chatty) or c["main"].as_bool("less_chatty")
         self.null_string = c["main"].get("null_string", "<null>")
         self.prompt_format = (
@@ -325,11 +334,11 @@ class PGCli(object):
             if pattern not in TabularOutputFormatter().supported_formats:
                 raise ValueError()
             self.table_format = pattern
-            yield (None, None, None, "Changed table format to {}".format(pattern))
+            yield (None, None, None, f"Changed table format to {pattern}")
         except ValueError:
-            msg = "Table format {} not recognized. Allowed formats:".format(pattern)
+            msg = f"Table format {pattern} not recognized. Allowed formats:"
             for table_type in TabularOutputFormatter().supported_formats:
-                msg += "\n\t{}".format(table_type)
+                msg += f"\n\t{table_type}"
             msg += "\nCurrently set to: %s" % self.table_format
             yield (None, None, None, msg)
 
@@ -386,10 +395,13 @@ class PGCli(object):
         try:
             with open(os.path.expanduser(pattern), encoding="utf-8") as f:
                 query = f.read()
-        except IOError as e:
+        except OSError as e:
             return [(None, None, None, str(e), "", False, True)]
 
-        if self.destructive_warning and confirm_destructive_query(query) is False:
+        if (
+            self.destructive_warning != "off"
+            and confirm_destructive_query(query, self.destructive_warning) is False
+        ):
             message = "Wise choice. Command execution stopped."
             return [(None, None, None, message)]
 
@@ -407,7 +419,7 @@ class PGCli(object):
         if not os.path.isfile(filename):
             try:
                 open(filename, "w").close()
-            except IOError as e:
+            except OSError as e:
                 self.output_file = None
                 message = str(e) + "\nFile output disabled"
                 return [(None, None, None, message, "", False, True)]
@@ -479,7 +491,7 @@ class PGCli(object):
         service_config, file = parse_service_info(service)
         if service_config is None:
             click.secho(
-                "service '%s' was not found in %s" % (service, file), err=True, fg="red"
+                f"service '{service}' was not found in {file}", err=True, fg="red"
             )
             exit(1)
         self.connect(
@@ -515,7 +527,7 @@ class PGCli(object):
             passwd = os.environ.get("PGPASSWORD", "")
 
         # Find password from store
-        key = "%s@%s" % (user, host)
+        key = f"{user}@{host}"
         keyring_error_message = dedent(
             """\
             {}
@@ -644,8 +656,10 @@ class PGCli(object):
         query = MetaQuery(query=text, successful=False)
 
         try:
-            if self.destructive_warning:
-                destroy = confirm = confirm_destructive_query(text)
+            if self.destructive_warning != "off":
+                destroy = confirm = confirm_destructive_query(
+                    text, self.destructive_warning
+                )
                 if destroy is False:
                     click.secho("Wise choice!")
                     raise KeyboardInterrupt
@@ -677,7 +691,7 @@ class PGCli(object):
                             click.echo(text, file=f)
                             click.echo("\n".join(output), file=f)
                             click.echo("", file=f)  # extra newline
-                    except IOError as e:
+                    except OSError as e:
                         click.secho(str(e), err=True, fg="red")
                 else:
                     if output:
@@ -729,7 +743,6 @@ class PGCli(object):
         if not self.less_chatty:
             print("Server: PostgreSQL", self.pgexecute.server_version)
             print("Version:", __version__)
-            print("Chat: https://gitter.im/dbcli/pgcli")
             print("Home: http://pgcli.com")
 
         try:
@@ -753,11 +766,7 @@ class PGCli(object):
                     while self.watch_command:
                         try:
                             query = self.execute_command(self.watch_command)
-                            click.echo(
-                                "Waiting for {0} seconds before repeating".format(
-                                    timing
-                                )
-                            )
+                            click.echo(f"Waiting for {timing} seconds before repeating")
                             sleep(timing)
                         except KeyboardInterrupt:
                             self.watch_command = None
@@ -979,16 +988,13 @@ class PGCli(object):
         callback = functools.partial(
             self._on_completions_refreshed, persist_priorities=persist_priorities
         )
-        self.completion_refresher.refresh(
+        return self.completion_refresher.refresh(
             self.pgexecute,
             self.pgspecial,
             callback,
             history=history,
             settings=self.settings,
         )
-        return [
-            (None, None, None, "Auto-completion refresh started in the background.")
-        ]
 
     def _on_completions_refreshed(self, new_completer, persist_priorities):
         self._swap_completer_objects(new_completer, persist_priorities)
@@ -1049,7 +1055,7 @@ class PGCli(object):
             str(self.pgexecute.port) if self.pgexecute.port is not None else "5432",
         )
         string = string.replace("\\i", str(self.pgexecute.pid) or "(none)")
-        string = string.replace("\\#", "#" if (self.pgexecute.superuser) else ">")
+        string = string.replace("\\#", "#" if self.pgexecute.superuser else ">")
         string = string.replace("\\n", "\n")
         return string
 
@@ -1075,9 +1081,10 @@ class PGCli(object):
     def echo_via_pager(self, text, color=None):
         if self.pgspecial.pager_config == PAGER_OFF or self.watch_command:
             click.echo(text, color=color)
-        elif "pspg" in os.environ.get("PAGER", "") and self.table_format == "csv":
-            click.echo_via_pager(text, color)
-        elif self.pgspecial.pager_config == PAGER_LONG_OUTPUT:
+        elif (
+            self.pgspecial.pager_config == PAGER_LONG_OUTPUT
+            and self.table_format != "csv"
+        ):
             lines = text.split("\n")
 
             # The last 4 lines are reserved for the pgcli menu and padding
@@ -1192,7 +1199,10 @@ class PGCli(object):
     help="Automatically switch to vertical output mode if the result is wider than the terminal width.",
 )
 @click.option(
-    "--warn/--no-warn", default=None, help="Warn before running a destructive query."
+    "--warn",
+    default=None,
+    type=click.Choice(["all", "moderate", "off"]),
+    help="Warn before running a destructive query.",
 )
 @click.argument("dbname", default=lambda: None, envvar="PGDATABASE", nargs=1)
 @click.argument("username", default=lambda: None, envvar="PGUSER", nargs=1)
@@ -1384,7 +1394,7 @@ def is_mutating(status):
     if not status:
         return False
 
-    mutating = set(["insert", "update", "delete"])
+    mutating = {"insert", "update", "delete"}
     return status.split(None, 1)[0].lower() in mutating
 
 
@@ -1475,7 +1485,12 @@ def format_output(title, cur, headers, status, settings):
             formatted = iter(formatted.splitlines())
         first_line = next(formatted)
         formatted = itertools.chain([first_line], formatted)
-        if not expanded and max_width and len(first_line) > max_width and headers:
+        if (
+            not expanded
+            and max_width
+            and len(strip_ansi(first_line)) > max_width
+            and headers
+        ):
             formatted = formatter.format_output(
                 cur, headers, format_name="vertical", column_types=None, **output_kwargs
             )
@@ -1502,10 +1517,16 @@ def parse_service_info(service):
             service_file = os.path.join(os.getenv("PGSYSCONFDIR"), ".pg_service.conf")
         else:
             service_file = expanduser("~/.pg_service.conf")
-    if not service:
+    if not service or not os.path.exists(service_file):
         # nothing to do
         return None, service_file
-    service_file_config = ConfigObj(service_file)
+    with open(service_file, newline="") as f:
+        skipped_lines = skip_initial_comment(f)
+        try:
+            service_file_config = ConfigObj(f)
+        except ParseError as err:
+            err.line_number += skipped_lines
+            raise err
     if service not in service_file_config:
         return None, service_file
     service_conf = service_file_config.get(service)
diff --git a/pgcli/packages/parseutils/__init__.py b/pgcli/packages/parseutils/__init__.py
index a11e7bf..1acc008 100644
--- a/pgcli/packages/parseutils/__init__.py
+++ b/pgcli/packages/parseutils/__init__.py
@@ -1,22 +1,34 @@
 import sqlparse
 
 
-def query_starts_with(query, prefixes):
+def query_starts_with(formatted_sql, prefixes):
     """Check if the query starts with any item from *prefixes*."""
     prefixes = [prefix.lower() for prefix in prefixes]
-    formatted_sql = sqlparse.format(query.lower(), strip_comments=True).strip()
     return bool(formatted_sql) and formatted_sql.split()[0] in prefixes
 
 
-def queries_start_with(queries, prefixes):
-    """Check if any queries start with any item from *prefixes*."""
-    for query in sqlparse.split(queries):
-        if query and query_starts_with(query, prefixes) is True:
-            return True
-    return False
+def query_is_unconditional_update(formatted_sql):
+    """Check if the query starts with UPDATE and contains no WHERE."""
+    tokens = formatted_sql.split()
+    return bool(tokens) and tokens[0] == "update" and "where" not in tokens
+
 
+def query_is_simple_update(formatted_sql):
+    """Check if the query starts with UPDATE."""
+    tokens = formatted_sql.split()
+    return bool(tokens) and tokens[0] == "update"
 
-def is_destructive(queries):
+
+def is_destructive(queries, warning_level="all"):
     """Returns if any of the queries in *queries* is destructive."""
     keywords = ("drop", "shutdown", "delete", "truncate", "alter")
-    return queries_start_with(queries, keywords)
+    for query in sqlparse.split(queries):
+        if query:
+            formatted_sql = sqlparse.format(query.lower(), strip_comments=True).strip()
+            if query_starts_with(formatted_sql, keywords):
+                return True
+            if query_is_unconditional_update(formatted_sql):
+                return True
+            if warning_level == "all" and query_is_simple_update(formatted_sql):
+                return True
+    return False
diff --git a/pgcli/packages/parseutils/meta.py b/pgcli/packages/parseutils/meta.py
index 108c01a..333cab5 100644
--- a/pgcli/packages/parseutils/meta.py
+++ b/pgcli/packages/parseutils/meta.py
@@ -50,7 +50,7 @@ def parse_defaults(defaults_string):
     yield current
 
 
-class FunctionMetadata(object):
+class FunctionMetadata:
     def __init__(
         self,
         schema_name,
diff --git a/pgcli/packages/parseutils/tables.py b/pgcli/packages/parseutils/tables.py
index 0ec3e69..aaa676c 100644
--- a/pgcli/packages/parseutils/tables.py
+++ b/pgcli/packages/parseutils/tables.py
@@ -42,8 +42,7 @@ def extract_from_part(parsed, stop_at_punctuation=True):
     for item in parsed.tokens:
         if tbl_prefix_seen:
             if is_subselect(item):
-                for x in extract_from_part(item, stop_at_punctuation):
-                    yield x
+                yield from extract_from_part(item, stop_at_punctuation)
             elif stop_at_punctuation and item.ttype is Punctuation:
                 return
             # An incomplete nested select won't be recognized correctly as a
diff --git a/pgcli/packages/pgliterals/pgliterals.json b/pgcli/packages/pgliterals/pgliterals.json
index c7b74b5..df00817 100644
--- a/pgcli/packages/pgliterals/pgliterals.json
+++ b/pgcli/packages/pgliterals/pgliterals.json
@@ -392,6 +392,7 @@
         "QUOTE_NULLABLE",
         "RADIANS",
         "RADIUS",
+        "RANDOM",
         "RANK",
         "REGEXP_MATCH",
         "REGEXP_MATCHES",
diff --git a/pgcli/packages/prioritization.py b/pgcli/packages/prioritization.py
index e92dcbb..f5a9cb5 100644
--- a/pgcli/packages/prioritization.py
+++ b/pgcli/packages/prioritization.py
@@ -16,10 +16,10 @@ def _compile_regex(keyword):
 
 
 keywords = get_literals("keywords")
-keyword_regexs = dict((kw, _compile_regex(kw)) for kw in keywords)
+keyword_regexs = {kw: _compile_regex(kw) for kw in keywords}
 
 
-class PrevalenceCounter(object):
+class PrevalenceCounter:
     def __init__(self):
         self.keyword_counts = defaultdict(int)
         self.name_counts = defaultdict(int)
diff --git a/pgcli/packages/prompt_utils.py b/pgcli/packages/prompt_utils.py
index 3c58490..e8589de 100644
--- a/pgcli/packages/prompt_utils.py
+++ b/pgcli/packages/prompt_utils.py
@@ -3,7 +3,7 @@ import click
 from .parseutils import is_destructive
 
 
-def confirm_destructive_query(queries):
+def confirm_destructive_query(queries, warning_level):
     """Check if the query is destructive and prompts the user to confirm.
 
     Returns:
@@ -15,7 +15,7 @@ def confirm_destructive_query(queries):
     prompt_text = (
         "You're about to run a destructive command.\n" "Do you want to proceed? (y/n)"
     )
-    if is_destructive(queries) and sys.stdin.isatty():
+    if is_destructive(queries, warning_level) and sys.stdin.isatty():
         return prompt(prompt_text, type=bool)
 
 
diff --git a/pgcli/packages/sqlcompletion.py b/pgcli/packages/sqlcompletion.py
index 6ef8859..6305301 100644
--- a/pgcli/packages/sqlcompletion.py
+++ b/pgcli/packages/sqlcompletion.py
@@ -47,7 +47,7 @@ Alias = namedtuple("Alias", ["aliases"])
 Path = namedtuple("Path", [])
 
 
-class SqlStatement(object):
+class SqlStatement:
     def __init__(self, full_text, text_before_cursor):
         self.identifier = None
         self.word_before_cursor = word_before_cursor = last_word(
diff --git a/pgcli/pgclirc b/pgcli/pgclirc
index e97afda..15c10f5 100644
--- a/pgcli/pgclirc
+++ b/pgcli/pgclirc
@@ -23,9 +23,13 @@ multi_line = False
 multi_line_mode = psql
 
 # Destructive warning mode will alert you before executing a sql statement
-# that may cause harm to the database such as "drop table", "drop database"
-# or "shutdown".
-destructive_warning = True
+# that may cause harm to the database such as "drop table", "drop database",
+# "shutdown", "delete", or "update".
+# Possible values:
+# "all" - warn on data definition statements, server actions such as SHUTDOWN, DELETE or UPDATE
+# "moderate" - skip warning on UPDATE statements, except for unconditional updates
+# "off" - skip all warnings
+destructive_warning = all
 
 # Enables expand mode, which is similar to `\x` in psql.
 expand = False
@@ -170,9 +174,12 @@ arg-toolbar = 'noinherit bold'
 arg-toolbar.text = 'nobold'
 bottom-toolbar.transaction.valid = 'bg:#222222 #00ff5f bold'
 bottom-toolbar.transaction.failed = 'bg:#222222 #ff005f bold'
-literal.string = '#ba2121'
-literal.number = '#666666'
-keyword = 'bold #008000'
+# These three values can be used to further refine the syntax highlighting.
+# They are commented out by default, since they have priority over the theme set
+# with the `syntax_style` setting and overriding its behavior can be confusing.
+# literal.string = '#ba2121'
+# literal.number = '#666666'
+# keyword = 'bold #008000'
 
 # style classes for colored table output
 output.header = "#00ff5f bold"
diff --git a/pgcli/pgcompleter.py b/pgcli/pgcompleter.py
index 9c95a01..227e25c 100644
--- a/pgcli/pgcompleter.py
+++ b/pgcli/pgcompleter.py
@@ -83,7 +83,7 @@ class PGCompleter(Completer):
     reserved_words = set(get_literals("reserved"))
 
     def __init__(self, smart_completion=True, pgspecial=None, settings=None):
-        super(PGCompleter, self).__init__()
+        super().__init__()
         self.smart_completion = smart_completion
         self.pgspecial = pgspecial
         self.prioritizer = PrevalenceCounter()
@@ -140,7 +140,7 @@ class PGCompleter(Completer):
         return "'{}'".format(self.unescape_name(name))
 
     def unescape_name(self, name):
-        """ Unquote a string."""
+        """Unquote a string."""
         if name and name[0] == '"' and name[-1] == '"':
             name = name[1:-1]
 
@@ -177,7 +177,7 @@ class PGCompleter(Completer):
         :return:
         """
         # casing should be a dict {lowercasename:PreferredCasingName}
-        self.casing = dict((word.lower(), word) for word in words)
+        self.casing = {word.lower(): word for word in words}
 
     def extend_relations(self, data, kind):
         """extend metadata for tables or views.
@@ -279,8 +279,8 @@ class PGCompleter(Completer):
             fk = ForeignKey(
                 parentschema, parenttable, parcol, childschema, childtable, childcol
             )
-            childcolmeta.foreignkeys.append((fk))
-            parcolmeta.foreignkeys.append((fk))
+            childcolmeta.foreignkeys.append(fk)
+            parcolmeta.foreignkeys.append(fk)
 
     def extend_datatypes(self, type_data):
 
@@ -424,7 +424,7 @@ class PGCompleter(Completer):
                 # the same priority as unquoted names.
                 lexical_priority = (
                     tuple(
-                        0 if c in (" _") else -ord(c)
+                        0 if c in " _" else -ord(c)
                         for c in self.unescape_name(item.lower())
                     )
                     + (1,)
@@ -517,9 +517,9 @@ class PGCompleter(Completer):
             # require_last_table is used for 'tb11 JOIN tbl2 USING (...' which should
             # suggest only columns that appear in the last table and one more
             ltbl = tables[-1].ref
-            other_tbl_cols = set(
+            other_tbl_cols = {
                 c.name for t, cs in scoped_cols.items() if t.ref != ltbl for c in cs
-            )
+            }
             scoped_cols = {
                 t: [col for col in cols if col.name in other_tbl_cols]
                 for t, cols in scoped_cols.items()
@@ -574,7 +574,7 @@ class PGCompleter(Completer):
         tbls - TableReference iterable of tables already in query
         """
         tbl = self.case(tbl)
-        tbls = set(normalize_ref(t.ref) for t in tbls)
+        tbls = {normalize_ref(t.ref) for t in tbls}
         if self.generate_aliases:
             tbl = generate_alias(self.unescape_name(tbl))
         if normalize_ref(tbl) not in tbls:
@@ -589,10 +589,10 @@ class PGCompleter(Completer):
         tbls = suggestion.table_refs
         cols = self.populate_scoped_cols(tbls)
         # Set up some data structures for efficient access
-        qualified = dict((normalize_ref(t.ref), t.schema) for t in tbls)
-        ref_prio = dict((normalize_ref(t.ref), n) for n, t in enumerate(tbls))
-        refs = set(normalize_ref(t.ref) for t in tbls)
-        other_tbls = set((t.schema, t.name) for t in list(cols)[:-1])
+        qualified = {normalize_ref(t.ref): t.schema for t in tbls}
+        ref_prio = {normalize_ref(t.ref): n for n, t in enumerate(tbls)}
+        refs = {normalize_ref(t.ref) for t in tbls}
+        other_tbls = {(t.schema, t.name) for t in list(cols)[:-1]}
         joins = []
         # Iterate over FKs in existing tables to find potential joins
         fks = (
@@ -667,7 +667,7 @@ class PGCompleter(Completer):
             return d
 
         # Tables that are closer to the cursor get higher prio
-        ref_prio = dict((tbl.ref, num) for num, tbl in enumerate(suggestion.table_refs))
+        ref_prio = {tbl.ref: num for num, tbl in enumerate(suggestion.table_refs)}
         # Map (schema, table, col) to tables
         coldict = list_dict(
             ((t.schema, t.name, c.name), t) for t, c in cols if t.ref != lref
@@ -703,7 +703,11 @@ class PGCompleter(Completer):
                     not f.is_aggregate
                     and not f.is_window
                     and not f.is_extension
-                    and (f.is_public or f.schema_name == suggestion.schema)
+                    and (
+                        f.is_public
+                        or f.schema_name in self.search_path
+                        or f.schema_name == suggestion.schema
+                    )
                 )
 
         else:
@@ -721,9 +725,7 @@ class PGCompleter(Completer):
         # Function overloading means we way have multiple functions of the same
         # name at this point, so keep unique names only
         all_functions = self.populate_functions(suggestion.schema, filt)
-        funcs = set(
-            self._make_cand(f, alias, suggestion, arg_mode) for f in all_functions
-        )
+        funcs = {self._make_cand(f, alias, suggestion, arg_mode) for f in all_functions}
 
         matches = self.find_matches(word_before_cursor, funcs, meta="function")
 
@@ -953,7 +955,7 @@ class PGCompleter(Completer):
         :return: {TableReference:{colname:ColumnMetaData}}
 
         """
-        ctes = dict((normalize_ref(t.name), t.columns) for t in local_tbls)
+        ctes = {normalize_ref(t.name): t.columns for t in local_tbls}
         columns = OrderedDict()
         meta = self.dbmetadata
 
diff --git a/pgcli/pgexecute.py b/pgcli/pgexecute.py
index d34bf26..a013b55 100644
--- a/pgcli/pgexecute.py
+++ b/pgcli/pgexecute.py
@@ -1,13 +1,15 @@
-import traceback
 import logging
+import select
+import traceback
+
+import pgspecial as special
 import psycopg2
-import psycopg2.extras
 import psycopg2.errorcodes
 import psycopg2.extensions as ext
+import psycopg2.extras
 import sqlparse
-import pgspecial as special
-import select
 from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE, make_dsn
+
 from .packages.parseutils.meta import FunctionMetadata, ForeignKey
 
 _logger = logging.getLogger(__name__)
@@ -27,6 +29,7 @@ ext.register_type(ext.new_type((17,), "BYTEA_TEXT", psycopg2.STRING))
 
 # TODO: Get default timeout from pgclirc?
 _WAIT_SELECT_TIMEOUT = 1
+_wait_callback_is_set = False
 
 
 def _wait_select(conn):
@@ -34,31 +37,41 @@ def _wait_select(conn):
     copy-pasted from psycopg2.extras.wait_select
     the default implementation doesn't define a timeout in the select calls
     """
-    while 1:
-        try:
-            state = conn.poll()
-            if state == POLL_OK:
-                break
-            elif state == POLL_READ:
-                select.select([conn.fileno()], [], [], _WAIT_SELECT_TIMEOUT)
-            elif state == POLL_WRITE:
-                select.select([], [conn.fileno()], [], _WAIT_SELECT_TIMEOUT)
-            else:
-                raise conn.OperationalError("bad state from poll: %s" % state)
-        except KeyboardInterrupt:
-            conn.cancel()
-            # the loop will be broken by a server error
-            continue
-        except select.error as e:
-            errno = e.args[0]
-            if errno != 4:
-                raise
+    try:
+        while 1:
+            try:
+                state = conn.poll()
+                if state == POLL_OK:
+                    break
+                elif state == POLL_READ:
+                    select.select([conn.fileno()], [], [], _WAIT_SELECT_TIMEOUT)
+                elif state == POLL_WRITE:
+                    select.select([], [conn.fileno()], [], _WAIT_SELECT_TIMEOUT)
+                else:
+                    raise conn.OperationalError("bad state from poll: %s" % state)
+            except KeyboardInterrupt:
+                conn.cancel()
+                # the loop will be broken by a server error
+                continue
+            except OSError as e:
+                errno = e.args[0]
+                if errno != 4:
+                    raise
+    except psycopg2.OperationalError:
+        pass
 
 
-# When running a query, make pressing CTRL+C raise a KeyboardInterrupt
-# See http://initd.org/psycopg/articles/2014/07/20/cancelling-postgresql-statements-python/
-# See also https://github.com/psycopg/psycopg2/issues/468
-ext.set_wait_callback(_wait_select)
+def _set_wait_callback(is_virtual_database):
+    global _wait_callback_is_set
+    if _wait_callback_is_set:
+        return
+    _wait_callback_is_set = True
+    if is_virtual_database:
+        return
+    # When running a query, make pressing CTRL+C raise a KeyboardInterrupt
+    # See http://initd.org/psycopg/articles/2014/07/20/cancelling-postgresql-statements-python/
+    # See also https://github.com/psycopg/psycopg2/issues/468
+    ext.set_wait_callback(_wait_select)
 
 
 def register_date_typecasters(connection):
@@ -72,6 +85,8 @@ def register_date_typecasters(connection):
 
     cursor = connection.cursor()
     cursor.execute("SELECT NULL::date")
+    if cursor.description is None:
+        return
     date_oid = cursor.description[0][1]
     cursor.execute("SELECT NULL::timestamp")
     timestamp_oid = cursor.description[0][1]
@@ -103,7 +118,7 @@ def register_json_typecasters(conn, loads_fn):
         try:
             psycopg2.extras.register_json(conn, loads=loads_fn, name=name)
             available.add(name)
-        except psycopg2.ProgrammingError:
+        except (psycopg2.ProgrammingError, psycopg2.errors.ProtocolViolation):
             pass
 
     return available
@@ -127,7 +142,39 @@ def register_hstore_typecaster(conn):
             pass
 
 
-class PGExecute(object):
+class ProtocolSafeCursor(psycopg2.extensions.cursor):
+    def __init__(self, *args, **kwargs):
+        self.protocol_error = False
+        self.protocol_message = ""
+        super().__init__(*args, **kwargs)
+
+    def __iter__(self):
+        if self.protocol_error:
+            raise StopIteration
+        return super().__iter__()
+
+    def fetchall(self):
+        if self.protocol_error:
+            return [(self.protocol_message,)]
+        return super().fetchall()
+
+    def fetchone(self):
+        if self.protocol_error:
+            return (self.protocol_message,)
+        return super().fetchone()
+
+    def execute(self, sql, args=None):
+        try:
+            psycopg2.extensions.cursor.execute(self, sql, args)
+            self.protocol_error = False
+            self.protocol_message = ""
+        except psycopg2.errors.ProtocolViolation as ex:
+            self.protocol_error = True
+            self.protocol_message = ex.pgerror
+            _logger.debug("%s: %s" % (ex.__class__.__name__, ex))
+
+
+class PGExecute:
 
     # The boolean argument to the current_schemas function indicates whether
     # implicit schemas, e.g. pg_catalog
@@ -190,8 +237,6 @@ class PGExecute(object):
         SELECT pg_catalog.pg_get_functiondef(f.f_oid)
         FROM f"""
 
-    version_query = "SELECT version();"
-
     def __init__(
         self,
         database=None,
@@ -203,6 +248,7 @@ class PGExecute(object):
         **kwargs,
     ):
         self._conn_params = {}
+        self._is_virtual_database = None
         self.conn = None
         self.dbname = None
         self.user = None
@@ -214,6 +260,11 @@ class PGExecute(object):
         self.connect(database, user, password, host, port, dsn, **kwargs)
         self.reset_expanded = None
 
+    def is_virtual_database(self):
+        if self._is_virtual_database is None:
+            self._is_virtual_database = self.is_protocol_error()
+        return self._is_virtual_database
+
     def copy(self):
         """Returns a clone of the current executor."""
         return self.__class__(**self._conn_params)
@@ -250,9 +301,9 @@ class PGExecute(object):
                 )
 
         conn_params.update({k: v for k, v in new_params.items() if v})
+        conn_params["cursor_factory"] = ProtocolSafeCursor
 
         conn = psycopg2.connect(**conn_params)
-        cursor = conn.cursor()
         conn.set_client_encoding("utf8")
 
         self._conn_params = conn_params
@@ -293,16 +344,22 @@ class PGExecute(object):
         self.extra_args = kwargs
 
         if not self.host:
-            self.host = self.get_socket_directory()
+            self.host = (
+                "pgbouncer"
+                if self.is_virtual_database()
+                else self.get_socket_directory()
+            )
 
-        pid = self._select_one(cursor, "select pg_backend_pid()")[0]
-        self.pid = pid
+        self.pid = conn.get_backend_pid()
         self.superuser = conn.get_parameter_status("is_superuser") in ("on", "1")
-        self.server_version = conn.get_parameter_status("server_version")
+        self.server_version = conn.get_parameter_status("server_version") or ""
+
+        _set_wait_callback(self.is_virtual_database())
 
-        register_date_typecasters(conn)
-        register_json_typecasters(self.conn, self._json_typecaster)
-        register_hstore_typecaster(self.conn)
+        if not self.is_virtual_database():
+            register_date_typecasters(conn)
+            register_json_typecasters(self.conn, self._json_typecaster)
+            register_hstore_typecaster(self.conn)
 
     @property
     def short_host(self):
@@ -395,7 +452,13 @@ class PGExecute(object):
                         # See https://github.com/dbcli/pgcli/issues/1014.
                         cur = None
                     try:
-                        for result in pgspecial.execute(cur, sql):
+                        response = pgspecial.execute(cur, sql)
+                        if cur and cur.protocol_error:
+                            yield None, None, None, cur.protocol_message, statement, False, False
+                            # this would close connection. We should reconnect.
+                            self.connect()
+                            continue
+                        for result in response:
                             # e.g. execute_from_file already appends these
                             if len(result) < 7:
                                 yield result + (sql, True, True)
@@ -453,6 +516,9 @@ class PGExecute(object):
         if cur.description:
             headers = [x[0] for x in cur.description]
             return title, cur, headers, cur.statusmessage
+        elif cur.protocol_error:
+            _logger.debug("Protocol error, unsupported command.")
+            return title, None, None, cur.protocol_message
         else:
             _logger.debug("No rows in result.")
             return title, None, None, cur.statusmessage
@@ -485,7 +551,7 @@ class PGExecute(object):
             try:
                 cur.execute(sql, (spec,))
             except psycopg2.ProgrammingError:
-                raise RuntimeError("View {} does not exist.".format(spec))
+                raise RuntimeError(f"View {spec} does not exist.")
             result = cur.fetchone()
             view_type = "MATERIALIZED" if result[2] == "m" else ""
             return template.format(*result + (view_type,))
@@ -501,7 +567,7 @@ class PGExecute(object):
                 result = cur.fetchone()
                 return result[0]
             except psycopg2.ProgrammingError:
-                raise RuntimeError("Function {} does not exist.".format(spec))
+                raise RuntimeError(f"Function {spec} does not exist.")
 
     def schemata(self):
         """Returns a list of schema names in the database"""
@@ -527,21 +593,18 @@ class PGExecute(object):
             sql = cur.mogrify(self.tables_query, [kinds])
             _logger.debug("Tables Query. sql: %r", sql)
             cur.execute(sql)
-            for row in cur:
-                yield row
+            yield from cur
 
     def tables(self):
         """Yields (schema_name, table_name) tuples"""
-        for row in self._relations(kinds=["r", "p", "f"]):
-            yield row
+        yield from self._relations(kinds=["r", "p", "f"])
 
     def views(self):
         """Yields (schema_name, view_name) tuples.
 
         Includes both views and and materialized views
         """
-        for row in self._relations(kinds=["v", "m"]):
-            yield row
+        yield from self._relations(kinds=["v", "m"])
 
     def _columns(self, kinds=("r", "p", "f", "v", "m")):
         """Get column metadata for tables and views
@@ -599,16 +662,13 @@ class PGExecute(object):
             sql = cur.mogrify(columns_query, [kinds])
             _logger.debug("Columns Query. sql: %r", sql)
             cur.execute(sql)
-            for row in cur:
-                yield row
+            yield from cur
 
     def table_columns(self):
-        for row in self._columns(kinds=["r", "p", "f"]):
-            yield row
+        yield from self._columns(kinds=["r", "p", "f"])
 
     def view_columns(self):
-        for row in self._columns(kinds=["v", "m"]):
-            yield row
+        yield from self._columns(kinds=["v", "m"])
 
     def databases(self):
         with self.conn.cursor() as cur:
@@ -623,6 +683,13 @@ class PGExecute(object):
             headers = [x[0] for x in cur.description]
             return cur.fetchall(), headers, cur.statusmessage
 
+    def is_protocol_error(self):
+        query = "SELECT 1"
+        with self.conn.cursor() as cur:
+            _logger.debug("Simple Query. sql: %r", query)
+            cur.execute(query)
+            return bool(cur.protocol_error)
+
     def get_socket_directory(self):
         with self.conn.cursor() as cur:
             _logger.debug(
@@ -804,8 +871,7 @@ class PGExecute(object):
                 """
             _logger.debug("Datatypes Query. sql: %r", query)
             cur.execute(query)
-            for row in cur:
-                yield row
+            yield from cur
 
     def casing(self):
         """Yields the most common casing for names used in db functions"""
diff --git a/pgcli/pgtoolbar.py b/pgcli/pgtoolbar.py
index f4289a1..41f903d 100644
--- a/pgcli/pgtoolbar.py
+++ b/pgcli/pgtoolbar.py
@@ -1,15 +1,23 @@
+from pkg_resources import packaging
+
+import prompt_toolkit
 from prompt_toolkit.key_binding.vi_state import InputMode
 from prompt_toolkit.application import get_app
 
+parse_version = packaging.version.parse
+
+vi_modes = {
+    InputMode.INSERT: "I",
+    InputMode.NAVIGATION: "N",
+    InputMode.REPLACE: "R",
+    InputMode.INSERT_MULTIPLE: "M",
+}
+if parse_version(prompt_toolkit.__version__) >= parse_version("3.0.6"):
+    vi_modes[InputMode.REPLACE_SINGLE] = "R"
+
 
 def _get_vi_mode():
-    return {
-        InputMode.INSERT: "I",
-        InputMode.NAVIGATION: "N",
-        InputMode.REPLACE: "R",
-        InputMode.REPLACE_SINGLE: "R",
-        InputMode.INSERT_MULTIPLE: "M",
-    }[get_app().vi_state.input_mode]
+    return vi_modes[get_app().vi_state.input_mode]
 
 
 def create_toolbar_tokens_func(pgcli):
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 80e8f43..84fa6bf 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,5 +1,4 @@
 pytest>=2.7.0
-mock>=1.0.1
 tox>=1.9.2
 behave>=1.2.4
 pexpect==3.3
diff --git a/tests/conftest.py b/tests/conftest.py
index 2a715b1..33cddf2 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -12,7 +12,7 @@ from utils import (
 import pgcli.pgexecute
 
 
-@pytest.yield_fixture(scope="function")
+@pytest.fixture(scope="function")
 def connection():
     create_db("_test_db")
     connection = db_connection("_test_db")
diff --git a/tests/features/db_utils.py b/tests/features/db_utils.py
index f57bc3b..6898394 100644
--- a/tests/features/db_utils.py
+++ b/tests/features/db_utils.py
@@ -44,7 +44,7 @@ def create_cn(hostname, password, username, dbname, port):
         host=hostname, user=username, database=dbname, password=password, port=port
     )
 
-    print("Created connection: {0}.".format(cn.dsn))
+    print(f"Created connection: {cn.dsn}.")
     return cn
 
 
@@ -75,4 +75,4 @@ def close_cn(cn=None):
     """
     if cn:
         cn.close()
-        print("Closed connection: {0}.".format(cn.dsn))
+        print(f"Closed connection: {cn.dsn}.")
diff --git a/tests/features/environment.py b/tests/features/environment.py
index 049c2f2..215c85c 100644
--- a/tests/features/environment.py
+++ b/tests/features/environment.py
@@ -38,7 +38,7 @@ def before_all(context):
 
     vi = "_".join([str(x) for x in sys.version_info[:3]])
     db_name = context.config.userdata.get("pg_test_db", "pgcli_behave_tests")
-    db_name_full = "{0}_{1}".format(db_name, vi)
+    db_name_full = f"{db_name}_{vi}"
 
     # Store get params from config.
     context.conf = {
@@ -63,7 +63,7 @@ def before_all(context):
                         "import coverage",
                         "coverage.process_startup()",
                         "import pgcli.main",
-                        "pgcli.main.cli()",
+                        "pgcli.main.cli(auto_envvar_prefix='BEHAVE')",
                     ]
                 ),
             )
@@ -102,6 +102,7 @@ def before_all(context):
     else:
         if "PGPASSWORD" in os.environ:
             del os.environ["PGPASSWORD"]
+    os.environ["BEHAVE_WARN"] = "moderate"
 
     context.cn = dbutils.create_db(
         context.conf["host"],
@@ -122,12 +123,12 @@ def before_all(context):
 def show_env_changes(env_old, env_new):
     """Print out all test-specific env values."""
     print("--- os.environ changed values: ---")
-    all_keys = set(list(env_old.keys()) + list(env_new.keys()))
+    all_keys = env_old.keys() | env_new.keys()
     for k in sorted(all_keys):
         old_value = env_old.get(k, "")
         new_value = env_new.get(k, "")
         if new_value and old_value != new_value:
-            print('{}="{}"'.format(k, new_value))
+            print(f'{k}="{new_value}"')
     print("-" * 20)
 
 
@@ -173,13 +174,13 @@ def after_scenario(context, scenario):
         # Quit nicely.
         if not context.atprompt:
             dbname = context.currentdb
-            context.cli.expect_exact("{0}> ".format(dbname), timeout=15)
+            context.cli.expect_exact(f"{dbname}> ", timeout=15)
         context.cli.sendcontrol("c")
         context.cli.sendcontrol("d")
         try:
             context.cli.expect_exact(pexpect.EOF, timeout=15)
         except pexpect.TIMEOUT:
-            print("--- after_scenario {}: kill cli".format(scenario.name))
+            print(f"--- after_scenario {scenario.name}: kill cli")
             context.cli.kill(signal.SIGKILL)
     if hasattr(context, "tmpfile_sql_help") and context.tmpfile_sql_help:
         context.tmpfile_sql_help.close()
diff --git a/tests/features/fixture_utils.py b/tests/features/fixture_utils.py
index 16f123a..70b603d 100644
--- a/tests/features/fixture_utils.py
+++ b/tests/features/fixture_utils.py
@@ -18,7 +18,7 @@ def read_fixture_files():
     """Read all files inside fixture_data directory."""
     current_dir = os.path.dirname(__file__)
     fixture_dir = os.path.join(current_dir, "fixture_data/")
-    print("reading fixture data: {}".format(fixture_dir))
+    print(f"reading fixture data: {fixture_dir}")
     fixture_dict = {}
     for filename in os.listdir(fixture_dir):
         if filename not in [".", ".."]:
diff --git a/tests/features/steps/basic_commands.py b/tests/features/steps/basic_commands.py
index 1069662..07e9ec1 100644
--- a/tests/features/steps/basic_commands.py
+++ b/tests/features/steps/basic_commands.py
@@ -65,19 +65,20 @@ def step_ctrl_d(context):
     Send Ctrl + D to hopefully exit.
     """
     # turn off pager before exiting
-    context.cli.sendline("\pset pager off")
+    context.cli.sendcontrol("c")
+    context.cli.sendline(r"\pset pager off")
     wrappers.wait_prompt(context)
     context.cli.sendcontrol("d")
     context.cli.expect(pexpect.EOF, timeout=15)
     context.exit_sent = True
 
 
-@when('we send "\?" command')
+@when(r'we send "\?" command')
 def step_send_help(context):
-    """
+    r"""
     Send \? to see help.
     """
-    context.cli.sendline("\?")
+    context.cli.sendline(r"\?")
 
 
 @when("we send partial select command")
@@ -96,9 +97,9 @@ def step_see_error_message(context):
 @when("we send source command")
 def step_send_source_command(context):
     context.tmpfile_sql_help = tempfile.NamedTemporaryFile(prefix="pgcli_")
-    context.tmpfile_sql_help.write(b"\?")
+    context.tmpfile_sql_help.write(br"\?")
     context.tmpfile_sql_help.flush()
-    context.cli.sendline("\i {0}".format(context.tmpfile_sql_help.name))
+    context.cli.sendline(fr"\i {context.tmpfile_sql_help.name}")
     wrappers.expect_exact(context, context.conf["pager_boundary"] + "\r\n", timeout=5)
 
 
diff --git a/tests/features/steps/crud_database.py b/tests/features/steps/crud_database.py
index 3fd8b7a..3f5d0e7 100644
--- a/tests/features/steps/crud_database.py
+++ b/tests/features/steps/crud_database.py
@@ -14,7 +14,7 @@ def step_db_create(context):
     """
     Send create database.
     """
-    context.cli.sendline("create database {0};".format(context.conf["dbname_tmp"]))
+    context.cli.sendline("create database {};".format(context.conf["dbname_tmp"]))
 
     context.response = {"database_name": context.conf["dbname_tmp"]}
 
@@ -24,7 +24,7 @@ def step_db_drop(context):
     """
     Send drop database.
     """
-    context.cli.sendline("drop database {0};".format(context.conf["dbname_tmp"]))
+    context.cli.sendline("drop database {};".format(context.conf["dbname_tmp"]))
 
 
 @when("we connect to test database")
@@ -33,7 +33,7 @@ def step_db_connect_test(context):
     Send connect to database.
     """
     db_name = context.conf["dbname"]
-    context.cli.sendline("\\connect {0}".format(db_name))
+    context.cli.sendline(f"\\connect {db_name}")
 
 
 @when("we connect to dbserver")
@@ -59,7 +59,7 @@ def step_see_prompt(context):
     Wait to see the prompt.
     """
     db_name = getattr(context, "currentdb", context.conf["dbname"])
-    wrappers.expect_exact(context, "{0}> ".format(db_name), timeout=5)
+    wrappers.expect_exact(context, f"{db_name}> ", timeout=5)
     context.atprompt = True
 
 
diff --git a/tests/features/steps/expanded.py b/tests/features/steps/expanded.py
index f34fcf0..265ea39 100644
--- a/tests/features/steps/expanded.py
+++ b/tests/features/steps/expanded.py
@@ -31,7 +31,7 @@ def step_prepare_data(context):
 @when("we set expanded {mode}")
 def step_set_expanded(context, mode):
     """Set expanded to mode."""
-    context.cli.sendline("\\" + "x {}".format(mode))
+    context.cli.sendline("\\" + f"x {mode}")
     wrappers.expect_exact(context, "Expanded display is", timeout=2)
     wrappers.wait_prompt(context)
 
diff --git a/tests/features/steps/iocommands.py b/tests/features/steps/iocommands.py
index 613aeb2..a614490 100644
--- a/tests/features/steps/iocommands.py
+++ b/tests/features/steps/iocommands.py
@@ -13,7 +13,7 @@ def step_edit_file(context):
     )
     if os.path.exists(context.editor_file_name):
         os.remove(context.editor_file_name)
-    context.cli.sendline("\e {0}".format(os.path.basename(context.editor_file_name)))
+    context.cli.sendline(r"\e {}".format(os.path.basename(context.editor_file_name)))
     wrappers.expect_exact(
         context, 'Entering Ex mode.  Type "visual" to go to Normal mode.', timeout=2
     )
@@ -53,7 +53,7 @@ def step_tee_ouptut(context):
     )
     if os.path.exists(context.tee_file_name):
         os.remove(context.tee_file_name)
-    context.cli.sendline("\o {0}".format(os.path.basename(context.tee_file_name)))
+    context.cli.sendline(r"\o {}".format(os.path.basename(context.tee_file_name)))
     wrappers.expect_exact(context, context.conf["pager_boundary"] + "\r\n", timeout=5)
     wrappers.expect_exact(context, "Writing to file", timeout=5)
     wrappers.expect_exact(context, context.conf["pager_boundary"] + "\r\n", timeout=5)
@@ -67,7 +67,7 @@ def step_query_select_123456(context):
 
 @when("we stop teeing output")
 def step_notee_output(context):
-    context.cli.sendline("\o")
+    context.cli.sendline(r"\o")
     wrappers.expect_exact(context, "Time", timeout=5)
 
 
diff --git a/tests/features/steps/specials.py b/tests/features/steps/specials.py
index 813292c..a85f371 100644
--- a/tests/features/steps/specials.py
+++ b/tests/features/steps/specials.py
@@ -22,5 +22,10 @@ def step_see_refresh_started(context):
     Wait to see refresh output.
     """
     wrappers.expect_pager(
-        context, "Auto-completion refresh started in the background.\r\n", timeout=2
+        context,
+        [
+            "Auto-completion refresh started in the background.\r\n",
+            "Auto-completion refresh restarted.\r\n",
+        ],
+        timeout=2,
     )
diff --git a/tests/features/steps/wrappers.py b/tests/features/steps/wrappers.py
index e0f5a20..0ca8366 100644
--- a/tests/features/steps/wrappers.py
+++ b/tests/features/steps/wrappers.py
@@ -39,9 +39,15 @@ def expect_exact(context, expected, timeout):
 
 
 def expect_pager(context, expected, timeout):
+    formatted = expected if isinstance(expected, list) else [expected]
+    formatted = [
+        f"{context.conf['pager_boundary']}\r\n{t}{context.conf['pager_boundary']}\r\n"
+        for t in formatted
+    ]
+
     expect_exact(
         context,
-        "{0}\r\n{1}{0}\r\n".format(context.conf["pager_boundary"], expected),
+        formatted,
         timeout=timeout,
     )
 
@@ -57,7 +63,7 @@ def run_cli(context, run_args=None, prompt_check=True, currentdb=None):
     context.cli.logfile = context.logfile
     context.exit_sent = False
     context.currentdb = currentdb or context.conf["dbname"]
-    context.cli.sendline("\pset pager always")
+    context.cli.sendline(r"\pset pager always")
     if prompt_check:
         wait_prompt(context)
 
diff --git a/tests/features/wrappager.py b/tests/features/wrappager.py
index 51d4909..51d4909 100755..100644
--- a/tests/features/wrappager.py
+++ b/tests/features/wrappager.py
diff --git a/tests/metadata.py b/tests/metadata.py
index 2f89ea2..4ebcccd 100644
--- a/tests/metadata.py
+++ b/tests/metadata.py
@@ -3,7 +3,7 @@ from itertools import product
 from pgcli.packages.parseutils.meta import FunctionMetadata, ForeignKey
 from prompt_toolkit.completion import Completion
 from prompt_toolkit.document import Document
-from mock import Mock
+from unittest.mock import Mock
 import pytest
 
 parametrize = pytest.mark.parametrize
@@ -59,7 +59,7 @@ def wildcard_expansion(cols, pos=-1):
     return Completion(cols, start_position=pos, display_meta="columns", display="*")
 
 
-class MetaData(object):
+class MetaData:
     def __init__(self, metadata):
         self.metadata = metadata
 
@@ -128,7 +128,7 @@ class MetaData(object):
         ]
 
     def schemas(self, pos=0):
-        schemas = set(sch for schs in self.metadata.values() for sch in schs)
+        schemas = {sch for schs in self.metadata.values() for sch in schs}
         return [schema(escape(s), pos=pos) for s in schemas]
 
     def functions_and_keywords(self, parent="public", pos=0):
diff --git a/tests/parseutils/test_parseutils.py b/tests/parseutils/test_parseutils.py
index 50bc889..5a375d7 100644
--- a/tests/parseutils/test_parseutils.py
+++ b/tests/parseutils/test_parseutils.py
@@ -1,4 +1,5 @@
 import pytest
+from pgcli.packages.parseutils import is_destructive
 from pgcli.packages.parseutils.tables import extract_tables
 from pgcli.packages.parseutils.utils import find_prev_keyword, is_open_quote
 
@@ -34,12 +35,12 @@ def test_simple_select_single_table_double_quoted():
 
 def test_simple_select_multiple_tables():
     tables = extract_tables("select * from abc, def")
-    assert set(tables) == set([(None, "abc", None, False), (None, "def", None, False)])
+    assert set(tables) == {(None, "abc", None, False), (None, "def", None, False)}
 
 
 def test_simple_select_multiple_tables_double_quoted():
     tables = extract_tables('select * from "Abc", "Def"')
-    assert set(tables) == set([(None, "Abc", None, False), (None, "Def", None, False)])
+    assert set(tables) == {(None, "Abc", None, False), (None, "Def", None, False)}
 
 
 def test_simple_select_single_table_deouble_quoted_aliased():
@@ -49,14 +50,12 @@ def test_simple_select_single_table_deouble_quoted_aliased():
 
 def test_simple_select_multiple_tables_deouble_quoted_aliased():
     tables = extract_tables('select * from "Abc" a, "Def" d')
-    assert set(tables) == set([(None, "Abc", "a", False), (None, "Def", "d", False)])
+    assert set(tables) == {(None, "Abc", "a", False), (None, "Def", "d", False)}
 
 
 def test_simple_select_multiple_tables_schema_qualified():
     tables = extract_tables("select * from abc.def, ghi.jkl")
-    assert set(tables) == set(
-        [("abc", "def", None, False), ("ghi", "jkl", None, False)]
-    )
+    assert set(tables) == {("abc", "def", None, False), ("ghi", "jkl", None, False)}
 
 
 def test_simple_select_with_cols_single_table():
@@ -71,14 +70,12 @@ def test_simple_select_with_cols_single_table_schema_qualified():
 
 def test_simple_select_with_cols_multiple_tables():
     tables = extract_tables("select a,b from abc, def")
-    assert set(tables) == set([(None, "abc", None, False), (None, "def", None, False)])
+    assert set(tables) == {(None, "abc", None, False), (None, "def", None, False)}
 
 
 def test_simple_select_with_cols_multiple_qualified_tables():
     tables = extract_tables("select a,b from abc.def, def.ghi")
-    assert set(tables) == set(
-        [("abc", "def", None, False), ("def", "ghi", None, False)]
-    )
+    assert set(tables) == {("abc", "def", None, False), ("def", "ghi", None, False)}
 
 
 def test_select_with_hanging_comma_single_table():
@@ -88,14 +85,12 @@ def test_select_with_hanging_comma_single_table():
 
 def test_select_with_hanging_comma_multiple_tables():
     tables = extract_tables("select a, from abc, def")
-    assert set(tables) == set([(None, "abc", None, False), (None, "def", None, False)])
+    assert set(tables) == {(None, "abc", None, False), (None, "def", None, False)}
 
 
 def test_select_with_hanging_period_multiple_tables():
     tables = extract_tables("SELECT t1. FROM tabl1 t1, tabl2 t2")
-    assert set(tables) == set(
-        [(None, "tabl1", "t1", False), (None, "tabl2", "t2", False)]
-    )
+    assert set(tables) == {(None, "tabl1", "t1", False), (None, "tabl2", "t2", False)}
 
 
 def test_simple_insert_single_table():
@@ -126,14 +121,14 @@ def test_simple_update_table_with_schema():
 
 @pytest.mark.parametrize("join_type", ["", "INNER", "LEFT", "RIGHT OUTER"])
 def test_join_table(join_type):
-    sql = "SELECT * FROM abc a {0} JOIN def d ON a.id = d.num".format(join_type)
+    sql = f"SELECT * FROM abc a {join_type} JOIN def d ON a.id = d.num"
     tables = extract_tables(sql)
-    assert set(tables) == set([(None, "abc", "a", False), (None, "def", "d", False)])
+    assert set(tables) == {(None, "abc", "a", False), (None, "def", "d", False)}
 
 
 def test_join_table_schema_qualified():
     tables = extract_tables("SELECT * FROM abc.def x JOIN ghi.jkl y ON x.id = y.num")
-    assert set(tables) == set([("abc", "def", "x", False), ("ghi", "jkl", "y", False)])
+    assert set(tables) == {("abc", "def", "x", False), ("ghi", "jkl", "y", False)}
 
 
 def test_incomplete_join_clause():
@@ -177,25 +172,25 @@ def test_extract_no_tables(text):
 
 @pytest.mark.parametrize("arg_list", ["", "arg1", "arg1, arg2, arg3"])
 def test_simple_function_as_table(arg_list):
-    tables = extract_tables("SELECT * FROM foo({0})".format(arg_list))
+    tables = extract_tables(f"SELECT * FROM foo({arg_list})")
     assert tables == ((None, "foo", None, True),)
 
 
 @pytest.mark.parametrize("arg_list", ["", "arg1", "arg1, arg2, arg3"])
 def test_simple_schema_qualified_function_as_table(arg_list):
-    tables = extract_tables("SELECT * FROM foo.bar({0})".format(arg_list))
+    tables = extract_tables(f"SELECT * FROM foo.bar({arg_list})")
     assert tables == (("foo", "bar", None, True),)
 
 
 @pytest.mark.parametrize("arg_list", ["", "arg1", "arg1, arg2, arg3"])
 def test_simple_aliased_function_as_table(arg_list):
-    tables = extract_tables("SELECT * FROM foo({0}) bar".format(arg_list))
+    tables = extract_tables(f"SELECT * FROM foo({arg_list}) bar")
     assert tables == ((None, "foo", "bar", True),)
 
 
 def test_simple_table_and_function():
     tables = extract_tables("SELECT * FROM foo JOIN bar()")
-    assert set(tables) == set([(None, "foo", None, False), (None, "bar", None, True)])
+    assert set(tables) == {(None, "foo", None, False), (None, "bar", None, True)}
 
 
 def test_complex_table_and_function():
@@ -203,9 +198,7 @@ def test_complex_table_and_function():
         """SELECT * FROM foo.bar baz
                                JOIN bar.qux(x, y, z) quux"""
     )
-    assert set(tables) == set(
-        [("foo", "bar", "baz", False), ("bar", "qux", "quux", True)]
-    )
+    assert set(tables) == {("foo", "bar", "baz", False), ("bar", "qux", "quux", True)}
 
 
 def test_find_prev_keyword_using():
@@ -267,3 +260,21 @@ def test_is_open_quote__closed(sql):
 )
 def test_is_open_quote__open(sql):
     assert is_open_quote(sql)
+
+
+@pytest.mark.parametrize(
+    ("sql", "warning_level", "expected"),
+    [
+        ("update abc set x = 1", "all", True),
+        ("update abc set x = 1 where y = 2", "all", True),
+        ("update abc set x = 1", "moderate", True),
+        ("update abc set x = 1 where y = 2", "moderate", False),
+        ("select x, y, z from abc", "all", False),
+        ("drop abc", "all", True),
+        ("alter abc", "all", True),
+        ("delete abc", "all", True),
+        ("truncate abc", "all", True),
+    ],
+)
+def test_is_destructive(sql, warning_level, expected):
+    assert is_destructive(sql, warning_level=warning_level) == expected
diff --git a/tests/test_completion_refresher.py b/tests/test_completion_refresher.py
index 6a916a8..a5529d6 100644
--- a/tests/test_completion_refresher.py
+++ b/tests/test_completion_refresher.py
@@ -1,6 +1,6 @@
 import time
 import pytest
-from mock import Mock, patch
+from unittest.mock import Mock, patch
 
 
 @pytest.fixture
@@ -37,7 +37,7 @@ def test_refresh_called_once(refresher):
     :return:
     """
     callbacks = Mock()
-    pgexecute = Mock()
+    pgexecute = Mock(**{"is_virtual_database.return_value": False})
     special = Mock()
 
     with patch.object(refresher, "_bg_refresh") as bg_refresh:
@@ -57,7 +57,7 @@ def test_refresh_called_twice(refresher):
     """
     callbacks = Mock()
 
-    pgexecute = Mock()
+    pgexecute = Mock(**{"is_virtual_database.return_value": False})
     special = Mock()
 
     def dummy_bg_refresh(*args):
@@ -84,14 +84,12 @@ def test_refresh_with_callbacks(refresher):
     :param refresher:
     """
     callbacks = [Mock()]
-    pgexecute_class = Mock()
-    pgexecute = Mock()
+    pgexecute = Mock(**{"is_virtual_database.return_value": False})
     pgexecute.extra_args = {}
     special = Mock()
 
-    with patch("pgcli.completion_refresher.PGExecute", pgexecute_class):
-        # Set refreshers to 0: we're not testing refresh logic here
-        refresher.refreshers = {}
-        refresher.refresh(pgexecute, special, callbacks)
-        time.sleep(1)  # Wait for the thread to work.
-        assert callbacks[0].call_count == 1
+    # Set refreshers to 0: we're not testing refresh logic here
+    refresher.refreshers = {}
+    refresher.refresh(pgexecute, special, callbacks)
+    time.sleep(1)  # Wait for the thread to work.
+    assert callbacks[0].call_count == 1
diff --git a/tests/test_config.py b/tests/test_config.py
index 1c023e0..08fe74e 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -1,9 +1,10 @@
+import io
 import os
 import stat
 
 import pytest
 
-from pgcli.config import ensure_dir_exists
+from pgcli.config import ensure_dir_exists, skip_initial_comment
 
 
 def test_ensure_file_parent(tmpdir):
@@ -20,11 +21,23 @@ def test_ensure_existing_dir(tmpdir):
 
 
 def test_ensure_other_create_error(tmpdir):
-    subdir = tmpdir.join("subdir")
+    subdir = tmpdir.join('subdir"')
     rcfile = subdir.join("rcfile")
 
-    # trigger an oserror that isn't "directory already exists"
+    # trigger an  oserror that isn't "directory already exists"
     os.chmod(str(tmpdir), stat.S_IREAD)
 
     with pytest.raises(OSError):
         ensure_dir_exists(str(rcfile))
+
+
+@pytest.mark.parametrize(
+    "text, skipped_lines",
+    (
+        ("abc\n", 1),
+        ("#[section]\ndef\n[section]", 2),
+        ("[section]", 0),
+    ),
+)
+def test_skip_initial_comment(text, skipped_lines):
+    assert skip_initial_comment(io.StringIO(text)) == skipped_lines
diff --git a/tests/test_main.py b/tests/test_main.py
index 9b85a34..c48accb 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -1,6 +1,6 @@
 import os
 import platform
-import mock
+from unittest import mock
 
 import pytest
 
@@ -288,7 +288,12 @@ def test_pg_service_file(tmpdir):
         cli = PGCli(pgclirc_file=str(tmpdir.join("rcfile")))
         with open(tmpdir.join(".pg_service.conf").strpath, "w") as service_conf:
             service_conf.write(
-                """[myservice]
+                """File begins with a comment
+            that is not a comment
+            # or maybe a comment after all
+            because psql is crazy
+
+            [myservice]
             host=a_host
             user=a_user
             port=5433
diff --git a/tests/test_naive_completion.py b/tests/test_naive_completion.py
index a6c80a7..5b93661 100644
--- a/tests/test_naive_completion.py
+++ b/tests/test_naive_completion.py
@@ -13,7 +13,7 @@ def completer():
 
 @pytest.fixture
 def complete_event():
-    from mock import Mock
+    from unittest.mock import Mock
 
     return Mock()
 
diff --git a/tests/test_pgexecute.py b/tests/test_pgexecute.py
index 9273be9..109674c 100644
--- a/tests/test_pgexecute.py
+++ b/tests/test_pgexecute.py
@@ -2,7 +2,7 @@ from textwrap import dedent
 
 import psycopg2
 import pytest
-from mock import patch, MagicMock
+from unittest.mock import patch, MagicMock
 from pgspecial.main import PGSpecial, NO_QUERY
 from utils import run, dbtest, requires_json, requires_jsonb
 
@@ -89,7 +89,7 @@ def test_expanded_slash_G(executor, pgspecial):
     # Tests whether we reset the expanded output after a \G.
     run(executor, """create table test(a boolean)""")
     run(executor, """insert into test values(True)""")
-    results = run(executor, """select * from test \G""", pgspecial=pgspecial)
+    results = run(executor, r"""select * from test \G""", pgspecial=pgspecial)
     assert pgspecial.expanded_output == False
 
 
@@ -105,31 +105,35 @@ def test_schemata_table_views_and_columns_query(executor):
     # schemata
     # don't enforce all members of the schemas since they may include postgres
     # temporary schemas
-    assert set(executor.schemata()) >= set(
-        ["public", "pg_catalog", "information_schema", "schema1", "schema2"]
-    )
+    assert set(executor.schemata()) >= {
+        "public",
+        "pg_catalog",
+        "information_schema",
+        "schema1",
+        "schema2",
+    }
     assert executor.search_path() == ["pg_catalog", "public"]
 
     # tables
-    assert set(executor.tables()) >= set(
-        [("public", "a"), ("public", "b"), ("schema1", "c")]
-    )
-
-    assert set(executor.table_columns()) >= set(
-        [
-            ("public", "a", "x", "text", False, None),
-            ("public", "a", "y", "text", False, None),
-            ("public", "b", "z", "text", False, None),
-            ("schema1", "c", "w", "text", True, "'meow'::text"),
-        ]
-    )
+    assert set(executor.tables()) >= {
+        ("public", "a"),
+        ("public", "b"),
+        ("schema1", "c"),
+    }
+
+    assert set(executor.table_columns()) >= {
+        ("public", "a", "x", "text", False, None),
+        ("public", "a", "y", "text", False, None),
+        ("public", "b", "z", "text", False, None),
+        ("schema1", "c", "w", "text", True, "'meow'::text"),
+    }
 
     # views
-    assert set(executor.views()) >= set([("public", "d")])
+    assert set(executor.views()) >= {("public", "d")}
 
-    assert set(executor.view_columns()) >= set(
-        [("public", "d", "e", "integer", False, None)]
-    )
+    assert set(executor.view_columns()) >= {
+        ("public", "d", "e", "integer", False, None)
+    }
 
 
 @dbtest
@@ -142,9 +146,9 @@ def test_foreign_key_query(executor):
         "create table schema2.child(childid int PRIMARY KEY, motherid int REFERENCES schema1.parent)",
     )
 
-    assert set(executor.foreignkeys()) >= set(
-        [("schema1", "parent", "parentid", "schema2", "child", "motherid")]
-    )
+    assert set(executor.foreignkeys()) >= {
+        ("schema1", "parent", "parentid", "schema2", "child", "motherid")
+    }
 
 
 @dbtest
@@ -175,30 +179,28 @@ def test_functions_query(executor):
     )
 
     funcs = set(executor.functions())
-    assert funcs >= set(
-        [
-            function_meta_data(func_name="func1", return_type="integer"),
-            function_meta_data(
-                func_name="func3",
-                arg_names=["x", "y"],
-                arg_types=["integer", "integer"],
-                arg_modes=["t", "t"],
-                return_type="record",
-                is_set_returning=True,
-            ),
-            function_meta_data(
-                schema_name="public",
-                func_name="func4",
-                arg_names=("x",),
-                arg_types=("integer",),
-                return_type="integer",
-                is_set_returning=True,
-            ),
-            function_meta_data(
-                schema_name="schema1", func_name="func2", return_type="integer"
-            ),
-        ]
-    )
+    assert funcs >= {
+        function_meta_data(func_name="func1", return_type="integer"),
+        function_meta_data(
+            func_name="func3",
+            arg_names=["x", "y"],
+            arg_types=["integer", "integer"],
+            arg_modes=["t", "t"],
+            return_type="record",
+            is_set_returning=True,
+        ),
+        function_meta_data(
+            schema_name="public",
+            func_name="func4",
+            arg_names=("x",),
+            arg_types=("integer",),
+            return_type="integer",
+            is_set_returning=True,
+        ),
+        function_meta_data(
+            schema_name="schema1", func_name="func2", return_type="integer"
+        ),
+    }
 
 
 @dbtest
@@ -257,8 +259,8 @@ def test_not_is_special(executor, pgspecial):
 
 @dbtest
 def test_execute_from_file_no_arg(executor, pgspecial):
-    """\i without a filename returns an error."""
-    result = list(executor.run("\i", pgspecial=pgspecial))
+    r"""\i without a filename returns an error."""
+    result = list(executor.run(r"\i", pgspecial=pgspecial))
     status, sql, success, is_special = result[0][3:]
     assert "missing required argument" in status
     assert success == False
@@ -268,12 +270,12 @@ def test_execute_from_file_no_arg(executor, pgspecial):
 @dbtest
 @patch("pgcli.main.os")
 def test_execute_from_file_io_error(os, executor, pgspecial):
-    """\i with an io_error returns an error."""
-    # Inject an IOError.
-    os.path.expanduser.side_effect = IOError("test")
+    r"""\i with an os_error returns an error."""
+    # Inject an OSError.
+    os.path.expanduser.side_effect = OSError("test")
 
     # Check the result.
-    result = list(executor.run("\i test", pgspecial=pgspecial))
+    result = list(executor.run(r"\i test", pgspecial=pgspecial))
     status, sql, success, is_special = result[0][3:]
     assert status == "test"
     assert success == False
@@ -290,7 +292,7 @@ def test_multiple_queries_same_line(executor):
 
 @dbtest
 def test_multiple_queries_with_special_command_same_line(executor, pgspecial):
-    result = run(executor, "select 'foo'; \d", pgspecial=pgspecial)
+    result = run(executor, r"select 'foo'; \d", pgspecial=pgspecial)
     assert len(result) == 11  # 2 * (output+status) * 3 lines
     assert "foo" in result[3]
     # This is a lame check. :(
@@ -408,7 +410,7 @@ def test_date_time_types(executor):
 @pytest.mark.parametrize("value", ["10000000", "10000000.0", "10000000000000"])
 def test_large_numbers_render_directly(executor, value):
     run(executor, "create table numbertest(a numeric)")
-    run(executor, "insert into numbertest (a) values ({0})".format(value))
+    run(executor, f"insert into numbertest (a) values ({value})")
     assert value in run(executor, "select * from numbertest", join=True)
 
 
@@ -511,13 +513,28 @@ def test_short_host(executor):
         assert executor.short_host == "localhost1"
 
 
-class BrokenConnection(object):
+class BrokenConnection:
     """Mock a connection that failed."""
 
     def cursor(self):
         raise psycopg2.InterfaceError("I'm broken!")
 
 
+class VirtualCursor:
+    """Mock a cursor to virtual database like pgbouncer."""
+
+    def __init__(self):
+        self.protocol_error = False
+        self.protocol_message = ""
+        self.description = None
+        self.status = None
+        self.statusmessage = "Error"
+
+    def execute(self, *args, **kwargs):
+        self.protocol_error = True
+        self.protocol_message = "Command not supported"
+
+
 @dbtest
 def test_exit_without_active_connection(executor):
     quit_handler = MagicMock()
@@ -540,3 +557,12 @@ def test_exit_without_active_connection(executor):
         # an exception should be raised when running a query without active connection
         with pytest.raises(psycopg2.InterfaceError):
             run(executor, "select 1", pgspecial=pgspecial)
+
+
+@dbtest
+def test_virtual_database(executor):
+    virtual_connection = MagicMock()
+    virtual_connection.cursor.return_value = VirtualCursor()
+    with patch.object(executor, "conn", virtual_connection):
+        result = run(executor, "select 1")
+        assert "Command not supported" in result
diff --git a/tests/test_pgspecial.py b/tests/test_pgspecial.py
index eaeaf12..cd99e32 100644
--- a/tests/test_pgspecial.py
+++ b/tests/test_pgspecial.py
@@ -13,12 +13,12 @@ from pgcli.packages.sqlcompletion import (
 
 def test_slash_suggests_special():
     suggestions = suggest_type("\\", "\\")
-    assert set(suggestions) == set([Special()])
+    assert set(suggestions) == {Special()}
 
 
 def test_slash_d_suggests_special():
     suggestions = suggest_type("\\d", "\\d")
-    assert set(suggestions) == set([Special()])
+    assert set(suggestions) == {Special()}
 
 
 def test_dn_suggests_schemata():
@@ -30,24 +30,24 @@ def test_dn_suggests_schemata():
 
 
 def test_d_suggests_tables_views_and_schemas():
-    suggestions = suggest_type("\d ", "\d ")
-    assert set(suggestions) == set([Schema(), Table(schema=None), View(schema=None)])
+    suggestions = suggest_type(r"\d ", r"\d ")
+    assert set(suggestions) == {Schema(), Table(schema=None), View(schema=None)}
 
-    suggestions = suggest_type("\d xxx", "\d xxx")
-    assert set(suggestions) == set([Schema(), Table(schema=None), View(schema=None)])
+    suggestions = suggest_type(r"\d xxx", r"\d xxx")
+    assert set(suggestions) == {Schema(), Table(schema=None), View(schema=None)}
 
 
 def test_d_dot_suggests_schema_qualified_tables_or_views():
-    suggestions = suggest_type("\d myschema.", "\d myschema.")
-    assert set(suggestions) == set([Table(schema="myschema"), View(schema="myschema")])
+    suggestions = suggest_type(r"\d myschema.", r"\d myschema.")
+    assert set(suggestions) == {Table(schema="myschema"), View(schema="myschema")}
 
-    suggestions = suggest_type("\d myschema.xxx", "\d myschema.xxx")
-    assert set(suggestions) == set([Table(schema="myschema"), View(schema="myschema")])
+    suggestions = suggest_type(r"\d myschema.xxx", r"\d myschema.xxx")
+    assert set(suggestions) == {Table(schema="myschema"), View(schema="myschema")}
 
 
 def test_df_suggests_schema_or_function():
     suggestions = suggest_type("\\df xxx", "\\df xxx")
-    assert set(suggestions) == set([Function(schema=None, usage="special"), Schema()])
+    assert set(suggestions) == {Function(schema=None, usage="special"), Schema()}
 
     suggestions = suggest_type("\\df myschema.xxx", "\\df myschema.xxx")
     assert suggestions == (Function(schema="myschema", usage="special"),)
@@ -63,7 +63,7 @@ def test_leading_whitespace_ok():
 def test_dT_suggests_schema_or_datatypes():
     text = "\\dT "
     suggestions = suggest_type(text, text)
-    assert set(suggestions) == set([Schema(), Datatype(schema=None)])
+    assert set(suggestions) == {Schema(), Datatype(schema=None)}
 
 
 def test_schema_qualified_dT_suggests_datatypes():
diff --git a/tests/test_prompt_utils.py b/tests/test_prompt_utils.py
index c1f8a16..a8a3a1e 100644
--- a/tests/test_prompt_utils.py
+++ b/tests/test_prompt_utils.py
@@ -7,4 +7,4 @@ def test_confirm_destructive_query_notty():
     stdin = click.get_text_stream("stdin")
     if not stdin.isatty():
         sql = "drop database foo;"
-        assert confirm_destructive_query(sql) is None
+        assert confirm_destructive_query(sql, "all") is None
diff --git a/tests/test_rowlimit.py b/tests/test_rowlimit.py
index e76ea04..947fc80 100644
--- a/tests/test_rowlimit.py
+++ b/tests/test_rowlimit.py
@@ -1,5 +1,5 @@
 import pytest
-from mock import Mock
+from unittest.mock import Mock
 
 from pgcli.main import PGCli
 
diff --git a/tests/test_smart_completion_multiple_schemata.py b/tests/test_smart_completion_multiple_schemata.py
index 805b727..5c9c9af 100644
--- a/tests/test_smart_completion_multiple_schemata.py
+++ b/tests/test_smart_completion_multiple_schemata.py
@@ -193,7 +193,7 @@ def test_suggested_joins(completer, query, tbl):
     result = get_result(completer, query.format(tbl))
     assert completions_to_set(result) == completions_to_set(
         testdata.schemas_and_from_clause_items()
-        + [join("custom.shipments ON shipments.user_id = {0}.id".format(tbl))]
+        + [join(f"custom.shipments ON shipments.user_id = {tbl}.id")]
     )
 
 
@@ -350,6 +350,36 @@ def test_schema_qualified_function_name(completer):
     )
 
 
+@parametrize("completer", completers(filtr=True, casing=False, aliasing=False))
+def test_schema_qualified_function_name_after_from(completer):
+    text = "SELECT * FROM custom.set_r"
+    result = get_result(completer, text)
+    assert completions_to_set(result) == completions_to_set(
+        [
+            function("set_returning_func()", -len("func")),
+        ]
+    )
+
+
+@parametrize("completer", completers(filtr=True, casing=False, aliasing=False))
+def test_unqualified_function_name_not_returned(completer):
+    text = "SELECT * FROM set_r"
+    result = get_result(completer, text)
+    assert completions_to_set(result) == completions_to_set([])
+
+
+@parametrize("completer", completers(filtr=True, casing=False, aliasing=False))
+def test_unqualified_function_name_in_search_path(completer):
+    completer.search_path = ["public", "custom"]
+    text = "SELECT * FROM set_r"
+    result = get_result(completer, text)
+    assert completions_to_set(result) == completions_to_set(
+        [
+            function("set_returning_func()", -len("func")),
+        ]
+    )
+
+
 @parametrize("completer", completers(filtr=True, casing=False))
 @parametrize(
     "text",
diff --git a/tests/test_smart_completion_public_schema_only.py b/tests/test_smart_completion_public_schema_only.py
index b935709..db1fe0a 100644
--- a/tests/test_smart_completion_public_schema_only.py
+++ b/tests/test_smart_completion_public_schema_only.py
@@ -53,7 +53,7 @@ metadata = {
     ],
 }
 
-metadata = dict((k, {"public": v}) for k, v in metadata.items())
+metadata = {k: {"public": v} for k, v in metadata.items()}
 
 testdata = MetaData(metadata)
 
@@ -296,7 +296,7 @@ def test_suggested_cased_always_qualified_column_names(completer):
 def test_suggested_column_names_in_function(completer):
     result = get_result(completer, "SELECT MAX( from users", len("SELECT MAX("))
     assert completions_to_set(result) == completions_to_set(
-        (testdata.columns_functions_and_keywords("users"))
+        testdata.columns_functions_and_keywords("users")
     )
 
 
@@ -316,7 +316,7 @@ def test_suggested_column_names_with_alias(completer):
 def test_suggested_multiple_column_names(completer):
     result = get_result(completer, "SELECT id,  from users u", len("SELECT id, "))
     assert completions_to_set(result) == completions_to_set(
-        (testdata.columns_functions_and_keywords("users"))
+        testdata.columns_functions_and_keywords("users")
     )
 
 
diff --git a/tests/test_sqlcompletion.py b/tests/test_sqlcompletion.py
index 3cbad0a..744fadb 100644
--- a/tests/test_sqlcompletion.py
+++ b/tests/test_sqlcompletion.py
@@ -23,16 +23,14 @@ def cols_etc(
 ):
     """Returns the expected select-clause suggestions for a single-table
     select."""
-    return set(
-        [
-            Column(
-                table_refs=(TableReference(schema, table, alias, is_function),),
-                qualifiable=True,
-            ),
-            Function(schema=parent),
-            Keyword(last_keyword),
-        ]
-    )
+    return {
+        Column(
+            table_refs=(TableReference(schema, table, alias, is_function),),
+            qualifiable=True,
+        ),
+        Function(schema=parent),
+        Keyword(last_keyword),
+    }
 
 
 def test_select_suggests_cols_with_visible_table_scope():
@@ -103,24 +101,20 @@ def test_where_equals_any_suggests_columns_or_keywords():
 
 def test_lparen_suggests_cols_and_funcs():
     suggestion = suggest_type("SELECT MAX( FROM tbl", "SELECT MAX(")
-    assert set(suggestion) == set(
-        [
-            Column(table_refs=((None, "tbl", None, False),), qualifiable=True),
-            Function(schema=None),
-            Keyword("("),
-        ]
-    )
+    assert set(suggestion) == {
+        Column(table_refs=((None, "tbl", None, False),), qualifiable=True),
+        Function(schema=None),
+        Keyword("("),
+    }
 
 
 def test_select_suggests_cols_and_funcs():
     suggestions = suggest_type("SELECT ", "SELECT ")
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=(), qualifiable=True),
-            Function(schema=None),
-            Keyword("SELECT"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=(), qualifiable=True),
+        Function(schema=None),
+        Keyword("SELECT"),
+    }
 
 
 @pytest.mark.parametrize(
@@ -128,13 +122,13 @@ def test_select_suggests_cols_and_funcs():
 )
 def test_suggests_tables_views_and_schemas(expression):
     suggestions = suggest_type(expression, expression)
-    assert set(suggestions) == set([Table(schema=None), View(schema=None), Schema()])
+    assert set(suggestions) == {Table(schema=None), View(schema=None), Schema()}
 
 
 @pytest.mark.parametrize("expression", ["SELECT * FROM "])
 def test_suggest_tables_views_schemas_and_functions(expression):
     suggestions = suggest_type(expression, expression)
-    assert set(suggestions) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestions) == {FromClauseItem(schema=None), Schema()}
 
 
 @pytest.mark.parametrize(
@@ -147,9 +141,11 @@ def test_suggest_tables_views_schemas_and_functions(expression):
 def test_suggest_after_join_with_two_tables(expression):
     suggestions = suggest_type(expression, expression)
     tables = tuple([(None, "foo", None, False), (None, "bar", None, False)])
-    assert set(suggestions) == set(
-        [FromClauseItem(schema=None, table_refs=tables), Join(tables, None), Schema()]
-    )
+    assert set(suggestions) == {
+        FromClauseItem(schema=None, table_refs=tables),
+        Join(tables, None),
+        Schema(),
+    }
 
 
 @pytest.mark.parametrize(
@@ -158,13 +154,11 @@ def test_suggest_after_join_with_two_tables(expression):
 def test_suggest_after_join_with_one_table(expression):
     suggestions = suggest_type(expression, expression)
     tables = ((None, "foo", None, False),)
-    assert set(suggestions) == set(
-        [
-            FromClauseItem(schema=None, table_refs=tables),
-            Join(((None, "foo", None, False),), None),
-            Schema(),
-        ]
-    )
+    assert set(suggestions) == {
+        FromClauseItem(schema=None, table_refs=tables),
+        Join(((None, "foo", None, False),), None),
+        Schema(),
+    }
 
 
 @pytest.mark.parametrize(
@@ -172,13 +166,13 @@ def test_suggest_after_join_with_one_table(expression):
 )
 def test_suggest_qualified_tables_and_views(expression):
     suggestions = suggest_type(expression, expression)
-    assert set(suggestions) == set([Table(schema="sch"), View(schema="sch")])
+    assert set(suggestions) == {Table(schema="sch"), View(schema="sch")}
 
 
 @pytest.mark.parametrize("expression", ["UPDATE sch."])
 def test_suggest_qualified_aliasable_tables_and_views(expression):
     suggestions = suggest_type(expression, expression)
-    assert set(suggestions) == set([Table(schema="sch"), View(schema="sch")])
+    assert set(suggestions) == {Table(schema="sch"), View(schema="sch")}
 
 
 @pytest.mark.parametrize(
@@ -193,26 +187,27 @@ def test_suggest_qualified_aliasable_tables_and_views(expression):
 )
 def test_suggest_qualified_tables_views_and_functions(expression):
     suggestions = suggest_type(expression, expression)
-    assert set(suggestions) == set([FromClauseItem(schema="sch")])
+    assert set(suggestions) == {FromClauseItem(schema="sch")}
 
 
 @pytest.mark.parametrize("expression", ["SELECT * FROM foo JOIN sch."])
 def test_suggest_qualified_tables_views_functions_and_joins(expression):
     suggestions = suggest_type(expression, expression)
     tbls = tuple([(None, "foo", None, False)])
-    assert set(suggestions) == set(
-        [FromClauseItem(schema="sch", table_refs=tbls), Join(tbls, "sch")]
-    )
+    assert set(suggestions) == {
+        FromClauseItem(schema="sch", table_refs=tbls),
+        Join(tbls, "sch"),
+    }
 
 
 def test_truncate_suggests_tables_and_schemas():
     suggestions = suggest_type("TRUNCATE ", "TRUNCATE ")
-    assert set(suggestions) == set([Table(schema=None), Schema()])
+    assert set(suggestions) == {Table(schema=None), Schema()}
 
 
 def test_truncate_suggests_qualified_tables():
     suggestions = suggest_type("TRUNCATE sch.", "TRUNCATE sch.")
-    assert set(suggestions) == set([Table(schema="sch")])
+    assert set(suggestions) == {Table(schema="sch")}
 
 
 @pytest.mark.parametrize(
@@ -220,13 +215,11 @@ def test_truncate_suggests_qualified_tables():
 )
 def test_distinct_suggests_cols(text):
     suggestions = suggest_type(text, text)
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=(), local_tables=(), qualifiable=True),
-            Function(schema=None),
-            Keyword("DISTINCT"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=(), local_tables=(), qualifiable=True),
+        Function(schema=None),
+        Keyword("DISTINCT"),
+    }
 
 
 @pytest.mark.parametrize(
@@ -244,20 +237,18 @@ def test_distinct_and_order_by_suggestions_with_aliases(
     text, text_before, last_keyword
 ):
     suggestions = suggest_type(text, text_before)
-    assert set(suggestions) == set(
-        [
-            Column(
-                table_refs=(
-                    TableReference(None, "tbl", "x", False),
-                    TableReference(None, "tbl1", "y", False),
-                ),
-                local_tables=(),
-                qualifiable=True,
+    assert set(suggestions) == {
+        Column(
+            table_refs=(
+                TableReference(None, "tbl", "x", False),
+                TableReference(None, "tbl1", "y", False),
             ),
-            Function(schema=None),
-            Keyword(last_keyword),
-        ]
-    )
+            local_tables=(),
+            qualifiable=True,
+        ),
+        Function(schema=None),
+        Keyword(last_keyword),
+    }
 
 
 @pytest.mark.parametrize(
@@ -272,56 +263,50 @@ def test_distinct_and_order_by_suggestions_with_aliases(
 )
 def test_distinct_and_order_by_suggestions_with_alias_given(text, text_before):
     suggestions = suggest_type(text, text_before)
-    assert set(suggestions) == set(
-        [
-            Column(
-                table_refs=(TableReference(None, "tbl", "x", False),),
-                local_tables=(),
-                qualifiable=False,
-            ),
-            Table(schema="x"),
-            View(schema="x"),
-            Function(schema="x"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(
+            table_refs=(TableReference(None, "tbl", "x", False),),
+            local_tables=(),
+            qualifiable=False,
+        ),
+        Table(schema="x"),
+        View(schema="x"),
+        Function(schema="x"),
+    }
 
 
 def test_function_arguments_with_alias_given():
     suggestions = suggest_type("SELECT avg(x. FROM tbl x, tbl2 y", "SELECT avg(x.")
 
-    assert set(suggestions) == set(
-        [
-            Column(
-                table_refs=(TableReference(None, "tbl", "x", False),),
-                local_tables=(),
-                qualifiable=False,
-            ),
-            Table(schema="x"),
-            View(schema="x"),
-            Function(schema="x"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(
+            table_refs=(TableReference(None, "tbl", "x", False),),
+            local_tables=(),
+            qualifiable=False,
+        ),
+        Table(schema="x"),
+        View(schema="x"),
+        Function(schema="x"),
+    }
 
 
 def test_col_comma_suggests_cols():
     suggestions = suggest_type("SELECT a, b, FROM tbl", "SELECT a, b,")
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "tbl", None, False),), qualifiable=True),
-            Function(schema=None),
-            Keyword("SELECT"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "tbl", None, False),), qualifiable=True),
+        Function(schema=None),
+        Keyword("SELECT"),
+    }
 
 
 def test_table_comma_suggests_tables_and_schemas():
     suggestions = suggest_type("SELECT a, b FROM tbl1, ", "SELECT a, b FROM tbl1, ")
-    assert set(suggestions) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestions) == {FromClauseItem(schema=None), Schema()}
 
 
 def test_into_suggests_tables_and_schemas():
     suggestion = suggest_type("INSERT INTO ", "INSERT INTO ")
-    assert set(suggestion) == set([Table(schema=None), View(schema=None), Schema()])
+    assert set(suggestion) == {Table(schema=None), View(schema=None), Schema()}
 
 
 @pytest.mark.parametrize(
@@ -357,14 +342,12 @@ def test_partially_typed_col_name_suggests_col_names():
 
 def test_dot_suggests_cols_of_a_table_or_schema_qualified_table():
     suggestions = suggest_type("SELECT tabl. FROM tabl", "SELECT tabl.")
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "tabl", None, False),)),
-            Table(schema="tabl"),
-            View(schema="tabl"),
-            Function(schema="tabl"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "tabl", None, False),)),
+        Table(schema="tabl"),
+        View(schema="tabl"),
+        Function(schema="tabl"),
+    }
 
 
 @pytest.mark.parametrize(
@@ -378,14 +361,12 @@ def test_dot_suggests_cols_of_a_table_or_schema_qualified_table():
 )
 def test_dot_suggests_cols_of_an_alias(sql):
     suggestions = suggest_type(sql, "SELECT t1.")
-    assert set(suggestions) == set(
-        [
-            Table(schema="t1"),
-            View(schema="t1"),
-            Column(table_refs=((None, "tabl1", "t1", False),)),
-            Function(schema="t1"),
-        ]
-    )
+    assert set(suggestions) == {
+        Table(schema="t1"),
+        View(schema="t1"),
+        Column(table_refs=((None, "tabl1", "t1", False),)),
+        Function(schema="t1"),
+    }
 
 
 @pytest.mark.parametrize(
@@ -399,28 +380,24 @@ def test_dot_suggests_cols_of_an_alias(sql):
 )
 def test_dot_suggests_cols_of_an_alias_where(sql):
     suggestions = suggest_type(sql, sql)
-    assert set(suggestions) == set(
-        [
-            Table(schema="t1"),
-            View(schema="t1"),
-            Column(table_refs=((None, "tabl1", "t1", False),)),
-            Function(schema="t1"),
-        ]
-    )
+    assert set(suggestions) == {
+        Table(schema="t1"),
+        View(schema="t1"),
+        Column(table_refs=((None, "tabl1", "t1", False),)),
+        Function(schema="t1"),
+    }
 
 
 def test_dot_col_comma_suggests_cols_or_schema_qualified_table():
     suggestions = suggest_type(
         "SELECT t1.a, t2. FROM tabl1 t1, tabl2 t2", "SELECT t1.a, t2."
     )
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "tabl2", "t2", False),)),
-            Table(schema="t2"),
-            View(schema="t2"),
-            Function(schema="t2"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "tabl2", "t2", False),)),
+        Table(schema="t2"),
+        View(schema="t2"),
+        Function(schema="t2"),
+    }
 
 
 @pytest.mark.parametrize(
@@ -452,20 +429,18 @@ def test_sub_select_partial_text_suggests_keyword(expression):
 def test_outer_table_reference_in_exists_subquery_suggests_columns():
     q = "SELECT * FROM foo f WHERE EXISTS (SELECT 1 FROM bar WHERE f."
     suggestions = suggest_type(q, q)
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "foo", "f", False),)),
-            Table(schema="f"),
-            View(schema="f"),
-            Function(schema="f"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "foo", "f", False),)),
+        Table(schema="f"),
+        View(schema="f"),
+        Function(schema="f"),
+    }
 
 
 @pytest.mark.parametrize("expression", ["SELECT * FROM (SELECT * FROM "])
 def test_sub_select_table_name_completion(expression):
     suggestion = suggest_type(expression, expression)
-    assert set(suggestion) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestion) == {FromClauseItem(schema=None), Schema()}
 
 
 @pytest.mark.parametrize(
@@ -478,22 +453,18 @@ def test_sub_select_table_name_completion(expression):
 def test_sub_select_table_name_completion_with_outer_table(expression):
     suggestion = suggest_type(expression, expression)
     tbls = tuple([(None, "foo", None, False)])
-    assert set(suggestion) == set(
-        [FromClauseItem(schema=None, table_refs=tbls), Schema()]
-    )
+    assert set(suggestion) == {FromClauseItem(schema=None, table_refs=tbls), Schema()}
 
 
 def test_sub_select_col_name_completion():
     suggestions = suggest_type(
         "SELECT * FROM (SELECT  FROM abc", "SELECT * FROM (SELECT "
     )
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "abc", None, False),), qualifiable=True),
-            Function(schema=None),
-            Keyword("SELECT"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "abc", None, False),), qualifiable=True),
+        Function(schema=None),
+        Keyword("SELECT"),
+    }
 
 
 @pytest.mark.xfail
@@ -508,25 +479,25 @@ def test_sub_select_dot_col_name_completion():
     suggestions = suggest_type(
         "SELECT * FROM (SELECT t. FROM tabl t", "SELECT * FROM (SELECT t."
     )
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "tabl", "t", False),)),
-            Table(schema="t"),
-            View(schema="t"),
-            Function(schema="t"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "tabl", "t", False),)),
+        Table(schema="t"),
+        View(schema="t"),
+        Function(schema="t"),
+    }
 
 
 @pytest.mark.parametrize("join_type", ("", "INNER", "LEFT", "RIGHT OUTER"))
 @pytest.mark.parametrize("tbl_alias", ("", "foo"))
 def test_join_suggests_tables_and_schemas(tbl_alias, join_type):
-    text = "SELECT * FROM abc {0} {1} JOIN ".format(tbl_alias, join_type)
+    text = f"SELECT * FROM abc {tbl_alias} {join_type} JOIN "
     suggestion = suggest_type(text, text)
     tbls = tuple([(None, "abc", tbl_alias or None, False)])
-    assert set(suggestion) == set(
-        [FromClauseItem(schema=None, table_refs=tbls), Schema(), Join(tbls, None)]
-    )
+    assert set(suggestion) == {
+        FromClauseItem(schema=None, table_refs=tbls),
+        Schema(),
+        Join(tbls, None),
+    }
 
 
 def test_left_join_with_comma():
@@ -535,9 +506,7 @@ def test_left_join_with_comma():
     # tbls should also include (None, 'bar', 'b', False)
     # but there's a bug with commas
     tbls = tuple([(None, "foo", "f", False)])
-    assert set(suggestions) == set(
-        [FromClauseItem(schema=None, table_refs=tbls), Schema()]
-    )
+    assert set(suggestions) == {FromClauseItem(schema=None, table_refs=tbls), Schema()}
 
 
 @pytest.mark.parametrize(
@@ -550,15 +519,13 @@ def test_left_join_with_comma():
 def test_join_alias_dot_suggests_cols1(sql):
     suggestions = suggest_type(sql, sql)
     tables = ((None, "abc", "a", False), (None, "def", "d", False))
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "abc", "a", False),)),
-            Table(schema="a"),
-            View(schema="a"),
-            Function(schema="a"),
-            JoinCondition(table_refs=tables, parent=(None, "abc", "a", False)),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "abc", "a", False),)),
+        Table(schema="a"),
+        View(schema="a"),
+        Function(schema="a"),
+        JoinCondition(table_refs=tables, parent=(None, "abc", "a", False)),
+    }
 
 
 @pytest.mark.parametrize(
@@ -570,14 +537,12 @@ def test_join_alias_dot_suggests_cols1(sql):
 )
 def test_join_alias_dot_suggests_cols2(sql):
     suggestion = suggest_type(sql, sql)
-    assert set(suggestion) == set(
-        [
-            Column(table_refs=((None, "def", "d", False),)),
-            Table(schema="d"),
-            View(schema="d"),
-            Function(schema="d"),
-        ]
-    )
+    assert set(suggestion) == {
+        Column(table_refs=((None, "def", "d", False),)),
+        Table(schema="d"),
+        View(schema="d"),
+        Function(schema="d"),
+    }
 
 
 @pytest.mark.parametrize(
@@ -598,9 +563,10 @@ on """,
 def test_on_suggests_aliases_and_join_conditions(sql):
     suggestions = suggest_type(sql, sql)
     tables = ((None, "abc", "a", False), (None, "bcd", "b", False))
-    assert set(suggestions) == set(
-        (JoinCondition(table_refs=tables, parent=None), Alias(aliases=("a", "b")))
-    )
+    assert set(suggestions) == {
+        JoinCondition(table_refs=tables, parent=None),
+        Alias(aliases=("a", "b")),
+    }
 
 
 @pytest.mark.parametrize(
@@ -613,9 +579,10 @@ def test_on_suggests_aliases_and_join_conditions(sql):
 def test_on_suggests_tables_and_join_conditions(sql):
     suggestions = suggest_type(sql, sql)
     tables = ((None, "abc", None, False), (None, "bcd", None, False))
-    assert set(suggestions) == set(
-        (JoinCondition(table_refs=tables, parent=None), Alias(aliases=("abc", "bcd")))
-    )
+    assert set(suggestions) == {
+        JoinCondition(table_refs=tables, parent=None),
+        Alias(aliases=("abc", "bcd")),
+    }
 
 
 @pytest.mark.parametrize(
@@ -640,9 +607,10 @@ def test_on_suggests_aliases_right_side(sql):
 def test_on_suggests_tables_and_join_conditions_right_side(sql):
     suggestions = suggest_type(sql, sql)
     tables = ((None, "abc", None, False), (None, "bcd", None, False))
-    assert set(suggestions) == set(
-        (JoinCondition(table_refs=tables, parent=None), Alias(aliases=("abc", "bcd")))
-    )
+    assert set(suggestions) == {
+        JoinCondition(table_refs=tables, parent=None),
+        Alias(aliases=("abc", "bcd")),
+    }
 
 
 @pytest.mark.parametrize(
@@ -659,9 +627,9 @@ def test_on_suggests_tables_and_join_conditions_right_side(sql):
 )
 def test_join_using_suggests_common_columns(text):
     tables = ((None, "abc", None, False), (None, "def", None, False))
-    assert set(suggest_type(text, text)) == set(
-        [Column(table_refs=tables, require_last_table=True)]
-    )
+    assert set(suggest_type(text, text)) == {
+        Column(table_refs=tables, require_last_table=True)
+    }
 
 
 def test_suggest_columns_after_multiple_joins():
@@ -678,29 +646,27 @@ def test_2_statements_2nd_current():
     suggestions = suggest_type(
         "select * from a; select * from ", "select * from a; select * from "
     )
-    assert set(suggestions) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestions) == {FromClauseItem(schema=None), Schema()}
 
     suggestions = suggest_type(
         "select * from a; select  from b", "select * from a; select "
     )
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "b", None, False),), qualifiable=True),
-            Function(schema=None),
-            Keyword("SELECT"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "b", None, False),), qualifiable=True),
+        Function(schema=None),
+        Keyword("SELECT"),
+    }
 
     # Should work even if first statement is invalid
     suggestions = suggest_type(
         "select * from; select * from ", "select * from; select * from "
     )
-    assert set(suggestions) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestions) == {FromClauseItem(schema=None), Schema()}
 
 
 def test_2_statements_1st_current():
     suggestions = suggest_type("select * from ; select * from b", "select * from ")
-    assert set(suggestions) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestions) == {FromClauseItem(schema=None), Schema()}
 
     suggestions = suggest_type("select  from a; select * from b", "select ")
     assert set(suggestions) == cols_etc("a", last_keyword="SELECT")
@@ -711,7 +677,7 @@ def test_3_statements_2nd_current():
         "select * from a; select * from ; select * from c",
         "select * from a; select * from ",
     )
-    assert set(suggestions) == set([FromClauseItem(schema=None), Schema()])
+    assert set(suggestions) == {FromClauseItem(schema=None), Schema()}
 
     suggestions = suggest_type(
         "select * from a; select  from b; select * from c", "select * from a; select "
@@ -768,13 +734,11 @@ SELECT * FROM qux;
 )
 def test_statements_in_function_body(text):
     suggestions = suggest_type(text, text[: text.find("  ") + 1])
-    assert set(suggestions) == set(
-        [
-            Column(table_refs=((None, "foo", None, False),), qualifiable=True),
-            Function(schema=None),
-            Keyword("SELECT"),
-        ]
-    )
+    assert set(suggestions) == {
+        Column(table_refs=((None, "foo", None, False),), qualifiable=True),
+        Function(schema=None),
+        Keyword("SELECT"),
+    }
 
 
 functions = [
@@ -799,13 +763,13 @@ SELECT 1 FROM foo;
 @pytest.mark.parametrize("text", functions)
 def test_statements_with_cursor_after_function_body(text):
     suggestions = suggest_type(text, text[: text.find("; ") + 1])
-    assert set(suggestions) == set([Keyword(), Special()])
+    assert set(suggestions) == {Keyword(), Special()}
 
 
 @pytest.mark.parametrize("text", functions)
 def test_statements_with_cursor_before_function_body(text):
     suggestions = suggest_type(text, "")
-    assert set(suggestions) == set([Keyword(), Special()])
+    assert set(suggestions) == {Keyword(), Special()}
 
 
 def test_create_db_with_template():
@@ -813,14 +777,14 @@ def test_create_db_with_template():
         "create database foo with template ", "create database foo with template "
     )
 
-    assert set(suggestions) == set((Database(),))
+    assert set(suggestions) == {Database()}
 
 
 @pytest.mark.parametrize("initial_text", ("", "    ", "\t \t", "\n"))
 def test_specials_included_for_initial_completion(initial_text):
     suggestions = suggest_type(initial_text, initial_text)
 
-    assert set(suggestions) == set([Keyword(), Special()])
+    assert set(suggestions) == {Keyword(), Special()}
 
 
 def test_drop_schema_qualified_table_suggests_only_tables():
@@ -843,25 +807,30 @@ def test_drop_schema_suggests_schemas():
 
 @pytest.mark.parametrize("text", ["SELECT x::", "SELECT x::y", "SELECT (x + y)::"])
 def test_cast_operator_suggests_types(text):
-    assert set(suggest_type(text, text)) == set(
-        [Datatype(schema=None), Table(schema=None), Schema()]
-    )
+    assert set(suggest_type(text, text)) == {
+        Datatype(schema=None),
+        Table(schema=None),
+        Schema(),
+    }
 
 
 @pytest.mark.parametrize(
     "text", ["SELECT foo::bar.", "SELECT foo::bar.baz", "SELECT (x + y)::bar."]
 )
 def test_cast_operator_suggests_schema_qualified_types(text):
-    assert set(suggest_type(text, text)) == set(
-        [Datatype(schema="bar"), Table(schema="bar")]
-    )
+    assert set(suggest_type(text, text)) == {
+        Datatype(schema="bar"),
+        Table(schema="bar"),
+    }
 
 
 def test_alter_column_type_suggests_types():
     q = "ALTER TABLE foo ALTER COLUMN bar TYPE "
-    assert set(suggest_type(q, q)) == set(
-        [Datatype(schema=None), Table(schema=None), Schema()]
-    )
+    assert set(suggest_type(q, q)) == {
+        Datatype(schema=None),
+        Table(schema=None),
+        Schema(),
+    }
 
 
 @pytest.mark.parametrize(
@@ -880,9 +849,11 @@ def test_alter_column_type_suggests_types():
     ],
 )
 def test_identifier_suggests_types_in_parentheses(text):
-    assert set(suggest_type(text, text)) == set(
-        [Datatype(schema=None), Table(schema=None), Schema()]
-    )
+    assert set(suggest_type(text, text)) == {
+        Datatype(schema=None),
+        Table(schema=None),
+        Schema(),
+    }
 
 
 @pytest.mark.parametrize(
@@ -977,7 +948,7 @@ def test_ignore_leading_double_quotes(sql):
 )
 def test_column_keyword_suggests_columns(sql):
     suggestions = suggest_type(sql, sql)
-    assert set(suggestions) == set([Column(table_refs=((None, "foo", None, False),))])
+    assert set(suggestions) == {Column(table_refs=((None, "foo", None, False),))}
 
 
 def test_handle_unrecognized_kw_generously():
diff --git a/tests/utils.py b/tests/utils.py
index 2427c30..460ea46 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -8,7 +8,7 @@ from os import getenv
 POSTGRES_USER = getenv("PGUSER", "postgres")
 POSTGRES_HOST = getenv("PGHOST", "localhost")
 POSTGRES_PORT = getenv("PGPORT", 5432)
-POSTGRES_PASSWORD = getenv("PGPASSWORD", "")
+POSTGRES_PASSWORD = getenv("PGPASSWORD", "postgres")
 
 
 def db_connection(dbname=None):
@@ -73,7 +73,7 @@ def drop_tables(conn):
 def run(
     executor, sql, join=False, expanded=False, pgspecial=None, exception_formatter=None
 ):
-    " Return string output for the sql to be run "
+    "Return string output for the sql to be run"
 
     results = executor.run(sql, pgspecial, exception_formatter)
     formatted = []
@@ -89,7 +89,7 @@ def run(
 
 
 def completions_to_set(completions):
-    return set(
+    return {
         (completion.display_text, completion.display_meta_text)
         for completion in completions
-    )
+    }